









































































































































































































I 

— T ( g = 

AUTONOBILE 

HANDBOOK 

A WORK OF PRACTICAL INF iM ATION FOR THE USE OF 


OWNERS, O 
AUTOMOBILE N 


fERATORS, 
ECHANICS AND 


TECHNlCAl 

SCHOOLS 

By LrELLIO 
Ncni Edition ReOi . 

By Calvin F. S 
And Other 

BROOKES 

d and Enlarged 

INGLE, M. E. 

Cxperts 

A strictly up-to-date treatise, dealin 
the various questions relating 
operation of gasoline, electric, 

in a practical manner with all 
o the construction, care and 
i id steam automobiles, includ- 


ing illustrated descriptions of thdmany different parts, together 
with clear and concise explanations of the principles governing 
their action. Correct methods are given for dealing with 

ROAD TROUBLES, MOTOR TH)UBLES, CARBURETOR 
TROUBLES and IGNLBON TROUBLES 


Also valuable information pertaining 
retors, magnetos etc.., etc. Valv< 
also indicator work, with numj 
formulas, and over three hundreqi 


to ignitation systems, carbu- 
setting is dealt with in detail, 
ous tables, useful rules and 
illustrations. 



CHICAGO 

FREDERICK .T. DRAKE & CO. 

PUBLISHERS 




445 











TL I5i 
33^ <b 


Cop;ight 1905 


BY 


FREDERICKJ. DRAKE & CO. 


Cop right 1907 


BY 


FREDERIC* J. DRAKE & CO. 


Copright 1910 
BY 

FREDERCK J. DRAKE 


Cop/right, 1913 


FREDERICI J. DRAKE & CO. 



©Cl. A3 4 6862 








INTRODUCTION 


Progress in the automobile industry in the United 
States during the past ten years has been phenomenal. 
The mechanical propulsion of a wheeled vehicle along 
an ordinary road is not by any means a new idea. 
History tells us that speculations upon the possible 
road use of ‘ ‘ fire, and steam engines ’ ’ were made by 
Roger Bacon (1214-1294), and in the year 1619 a pat¬ 
ent was granted in England to Ramsay, which had as 
a part of its subject “ drawing carts without horses. ” 
Many attempts were made from that time on to perfect- 
a self-propelling road vehicle, using steam as the pro¬ 
pelling force, but it was not until the end of the year 
1883 that Delamare-Debouttville constructed what is 
thought to be the first gas tricycle which actually ran 
on a public road. The general employment of gasoline 
motors is due to two Frenchmen, Levassor, and Pan- 
hard, who in 1889 exhibited in Paris a tram car having 
a Daimler motor. Since then the development of the 
gasoline motor car has been remarkable, due no doubt 
to the fact that some of the best engineering talent in 
the world has been, and is at present being directed 
toward the perfection of the various types of auto¬ 
mobiles, and it is entirely within the bounds of reason 
to expect that a machine requiring so high a grade of 
talent for its design and construction, should in its 
operation be under the care of a skilled and reliable 
chauffeur, one who not only understands the principles 
of operation of each and all of the various parts 
which go to make up the whole, but who also is com¬ 
petent in case of minor accidents on the road, to make 
such repairs as will enable him to proceed. He also 
should be able to make such adjustments, and give the 
machine such care as to reduce the expense of main¬ 
tenance to a minimum. It is with a view of assisting 
owners and drivers of automobiles, in fact all who are 
in any way interested in a study ©f this remarkable, 
and at the same time most useful machine, that the 
Automobile Hand Book has been rewritten and revised, 
thus bringing it strictly up to date, and in touch with 
modern practice in the art of automobiling. Wnile a 


The Automobile Handbook 


considerable portion of the subject matter found in 
former editions of the book has been retained for the 
reason that it is standard, by far the larger portion of 
the volume is new matter, and embodies the most recent 
improvements in automobiles, together with instructions 
concerning their care and operation. Each part of the 
machine is thoroughly treated upon, and its construc¬ 
tion and the principles governing its operation are ex¬ 
plained and illustrated in detail. While the gasoline 
motor with its various accessories naturally occupies 
the major portion of the book, still a considerable 
space is devoted to steam, and electric motor cars. 
Special attention is given to ignition mechanism in¬ 
cluding the various types of carbureters, magnetos, 
etc., all being clearly described and illustrated. Trans¬ 
mission apparatus of all kinds is dealt with in detail. 
Wheel construction receives a large share of attention, 
and the important subject of tires is freely discussed. 

A large space is given to repair work in the shop, 
and garage. As the subject of state license law T s con¬ 
templating the appearance of the chauffeur before an 
examining board is one in which all motorists are 
vitally interested, this book will prove to be a reliable 
and trustworthy guide to all persons taking such 
examinations. 

Note—The author gratefully acknowledges his in¬ 
debtedness to the following named gentlemen, con¬ 
sulting engineers, and authors of standard works on 
engineering subjects: 

Oscar C. Schmidt, consulting editor American Text 
Book Co., author of Practical Treatise on Automobiles. 

Paul N. Hasluck, author of Construction of Modern 
Motor Cars. 

The International Text Book Company, Scranton. 


The Automobile Handbook 


Acetylene. A number of inconveniences are 
attached to the use of acetylene. The problem 
of properly purifying it has yet to be solved. 
Metallic compounds of sulphur, phosphorus and 
nitrogen and free carbon are contained in the 
carbide, and the gas has in it many impurities 
which endanger health when burned in closed 
rooms. The free carbon in the carbide gets into 
the burners in the form of fine dust and ob¬ 
structs them. A great annoyance is smoking of 
the lamps, which takes place after two or three 
hours burning. This is due to decomposition of 
the acetylene by the heated burner, by which 
carbon is deposited in the narrow opening. 
Many of the so-called spontaneous explosions 
of this gas have without doubt been caused by 
high temperature in the generator. 

Acetylene Lamp System—Care of. As there 
is little night running during the winter 
months, the acetylene lighting system is more 
or less neglected, the generator being left with 
stale or partially used carbide in the chamber, 
and the residue being allowed to clog up the 
water port and the waste ports. The rubber 

7 



The Automobile Handbook 


8 

lamp connections and gas-bag suffer also by de¬ 
terioration as well as the burners and gas valves. 
For the proper maintenance of the system, strict 
cleanliness should be maintained at all times, 
and the various parts should be examined and 
replaced from time to time as necessary. The 
results of neglect are seen every spring in lime 
deposits which have to be removed by means of 
a cold chisel, in porous connections and in 
clogged burners which resist the cleaning wire 
and necessitate the scraping of the burners. By 
following* the accompanying directions, the au- 
tomobilist can depend on having his lighting 
system in good shape whenever he desires to 
use it. 

Acid Solutions. The electrolyte, or solution 
used in storage battery cells, is made by pour¬ 
ing sulphuric acid into distilled water until the 
specific gravity becomes 1.32. The solution be¬ 
comes extremely warm and should not be used 
until its temperature is about 60 degrees. 

Accumulators. The accumulator or storage 
battery is the only source of electrical energy 
of practical use for driving an automobile, be¬ 
cause an electrically propelled car, like other 
automobiles, must self-con tain its supply of en¬ 
ergy, and thus it excludes employment of the 
trolley running under a conductor in constant 
communication with generators at the power 
station. 

The accumulators used in electric automobiles 
are adaptations of the storage batteries used for 


The Automobile Handbook 


9 


electric lighting, but are much lighter and give 
a greater output, weight for weight; they are 
also made to bear over-discharge, and the wear 
and tear of rough travelling. The active agents 
in general use are lead and dilute sulphuric 
acid. 

Accumulators may be divided broadly into 
two classes; namely, the “to-be-formed,” or 
Plante kind (1873) ; and the “pasted,” or 
formed Faure kind (1881). The object of both 
processes is to produce a couple consisting of a 
positive electrode of lead oxide, and a negative 
electrode of lead in a solution of sulphuric acid 
and water. Peroxide of lead is formed on the 
positive, and pure lead on the negative, by the 
process of charging; and energy is stored which 
is given up on discharging the battery, when 
the electrodes return to their first state of lead 
sulphate. The pasted cell is lighter than the 
other, and is more generally used in electric 
automobiles. This subject will be further 
treated upon under the head of Storage Bat¬ 
teries. 

Acceleration. The increase of motion, or ac¬ 
tion. The time period of mutation in velocity. 

Acetometer, or Acidometer. A graduated 
hydrometer used to ascertain the strength of 
acetic acid, or vinegar. 

Active Coil, or Conductor. A coil, or con¬ 
ductor, conveying a current of electricity. 

Adams Revolving Cylinder Motor. The 
Adams motor rated at 50 horse power has a five 


10 


The Automobile Handbook 


cylinder engine with a bore and stroke of 5V2 
and 5 inches. In this motor the crankshaft is 
mounted vertically and has but one throw, the 
same as ordinarily used for a single-cylinder 
engine. This crankshaft is stationary—it never 
revolves, but the five cylinders revolve around 
it, as does the front wheel of a motor car on 
the steering spindle. The car is without a radi¬ 
ator, being an air-cooled machine; as the mo¬ 
tor cylinders revolve, a cooling fan is not 
needed. It is without a muffler, each cylinder 
exhausting directly into a box which incloses 
the motor. The motor is directly above the 
transmission set, and as the motor is without 
a flywheel of any sort, it has been necessary for 
the designer to carry the double cone clutch 
within the selective gear set. The drive from 
the revolving cylinders to the gear-set is 
through a bevel gear attached to the base of 
the revolving crank case, and which meshes 
with a bevel gear on one of the transverse 
shafts of the transmission. From the transmis¬ 
sion to the rear axle, a chain drive is employed. 
This car is without a float feed carbureter, but 
uses instead, a pump to maintain a gasoline 
level in a chamber in which a spraying nozzle 
and an air valve complete the carbureter. In¬ 
stead of controlling the motor speed by advanc¬ 
ing or retarding the spark, and opening and 
closing the throttle, it is done by controlling 
the length of time each intake valve is held 
open. This motor has but one cam to open all 


The Automobile Handbook 


11 


of the ten valves. This cam being in two parts, 
it is possible to shift one, thereby varying the 
length of opening given a valve, and allowing 
a part of the mixture drawn into a cylinder to 
escape during a compression stroke, so that the 
explosive pressure can be varied from 90 lbs. 
to 0, and the power of the motor, and its speed 



Fig. l 

Sectional A iew of Adams Motor 


correspondingly varied. There is no branching 
manifold to convey the mixture to the cylin¬ 
ders, neither is there an exhaust manifold. 

In Fig. 1 is a sectional view of the motor with 
its five cylinders designated respectively 1, 2, 3, 
4 and 5, with five pistons shown in relative po¬ 
sition. The crankshaft A has its one offset B. 
As each cylinder makes, in unison with the 


























12 


The Automobile Handbook 


other four, two complete revolutions, it passes 
through the four cycles of operation common 
to any four-cycle engine—inspiration, compres¬ 
sion, explosion, exhaust. No. 4 cylinder is 
shown at the end of the out stroke, and the 
other four at different parts of the stroke; and 
as each in succession occupies the position of 



Cam Diagram—Adams Revolving Cylinder Motor 

No. 4, its piston will be at the end of the out 
stroke. When diametrically opposite to No. 4 
they will be at the inner end of the stroke. 
Thus, as the five cylinders bolted firmly to¬ 
gether to a hublike crankcase revolve, the pis¬ 
tons reciprocate in the cylinders, thus perform¬ 
ing in perfect sequence, the four functions of 
cycling. The valves are located in the cylinder 

















The Automobile Handbook 


13 


heads and opened by rocker arms with push 
rods paralleling the cylinders on their lower 
sides. One diagram illustrates the single cam 
construction and valve operation. On the loAver 
end of the crankshaft is the two-part cam C, 
Cl—Fig. 2. The latter, shown in dotted line, 
is the movable half for controlling the intake 
valve period of opening. Both parts of the 
cam are stationary. On each of the five cylin¬ 
ders is a push rod P, the inner end of which has 


i 


Fig. 3 

Adams Four-Feed Oiler 

a peculiar foot P2 pivoted on the crankcase 
with the curve portion bearing upon the cam, 
and the short straight arm connected with the 
push rod P. As the cylinder revolves, the 
rounded foot follows the contour of the cam, 
which has been designed so that the four cycles 
follow one another in order as they do in a four¬ 
cycle vertical engine. 

The oiler employed on the motor is a four- 
feed plunger type, the four plungers being car- 





























































14 


The Automobile Handbook 


ried in a rotating* member, with the recipro¬ 
cation of the plunger produced by two end cams. 
The sectional illustration, Fig. 3, shows the 
casing A, the rotating member driven by gear. 
Two plungers D appear, and at their ends ar.e 
the cams E and F, cam E to force each plunger 
in turn toward the right, and cam F to force it 
leftward. Revolving, the cylinder brings each 
plunger D in turn around so the opening G, 



Fig. 4 

Adams Three-Speed Selective Set Containing Cone Clutch 


through which oil is drawn into the cylinder 
when the plunger is pushed out by the cam F. 
registers with a port. As the cylinder revolves 
the opening G soon will register wtih the out¬ 
let opening GI, at which time the cam E, forcing 
the plunger D rightward, sends two drops of 
oil through the lead GI to a bearing. Each of 
the four plungers has its openings G, and GI 
for taking in oil and delivering it to the oil 
leads. 




The Automobile Handbook 


15 


The selective transmission shown in Fig. 4 
has its shaft located transversely of the car, car¬ 
rying the doublecone clutch M within it and 
driving by single chain from a sprocket S at 
one end. The bevel gear K constantly meshes 
with the bevel on the crankcase, and so receives 
the power from the motor. The reader should 
follow how the power passes from the bevel K 
to the sprocket S through the mechanisms of 
the gearset. The bevel K, and the external part 
of the clutch M are on a sleeve, whereas the 
gear A, and the internal part of the clutch are 
on the shaft carrying the sleeve. This shaft is 
in alignment with the shaft Y, and can be cou¬ 
pled with it by jaw clutch B. To get direct 
drive gear C is moved to gear A as illustrated, 
the jaw clutch B coupling the shaft Y with the 
shaft carrying the clutch M. This done, en¬ 
gaging the clutch M locks the gear K to the 
shaft Y on which is the sprocket S for chain 
drive. For intermediate speed, gears E and 
A are meshed, and also gears C and F, the 
jiower then passing to the countershaft X and 
then back to the squared shaft Y carrying the 
sprocket S. For slow speed gears A and E 
transfer to the countershaft, and gears D and 
G transfer to the shaft Y. In reversing G 
meshes with the idler H, which is of sufficiently 
wide face to also mesh with gear D when it is 
moved endwise. When not in use the idler II 
does not revolve. The clutch M is of the dou¬ 
ble-cone type. The central cone is of bronze 



Chassis of Adams-Farwell Car with Its Five-Cylinder Revolving Star Motor 























The Automobile Handbook 


17 


with cork inserts, and the external and internal 
cones of cast iron. The eccentric 0 is for driv¬ 
ing the gasoline pump supplying the carbu¬ 
reter. The housing N covers a ratchet wheel 
keyed to the shaft carrying the gear A and is 
connected to the driver’s seat so the motor can 
be cranked through the gearset. 

Fig. 5 is a plan view of the chassis, showing 
the mechanism of the car complete. 



Fig. o 


Admission-pipes, Diameter of. The internal 
diameter of the admission or inlet-pipe leading 
from the carbureter to the admission-valve 
chamber should not exceed one-fourth the diam¬ 
eter of the motor cylinder. 

This limitation is necessary in order to pro¬ 
duce as great a partial vacuum as is possible in 
the admission-pipe. The carbureter should be 
placed as close as possible to the admission- 
valve chamber of the mAtcr in order to secure 
































18 


The Automobile Handbook 


the best results. Short turns or bends in the 
admission-pipe greatly increase the air-friction 
in the pipe, and at high speeds greatly diminish 
the volume of the charge drawn into the cylin¬ 
der by the inductive or suction action of the 
motor-piston. An admission-pipe with a side 
inlet and short bends, for a two-cylinder motor, 
is shown in Figure 6. Such forms of construc- 



Fig. 7 

tion should be avoided whenever possible. Fig¬ 
ure 7 shows an admission-pipe of approved de¬ 
sign, with long bends, for a two-cylinder motor. 
The radius of curvature of the pipe on its cen¬ 
ter line should not be less than twice the out¬ 
side diameter of the pipe. If space allows, a 
radius of three times the outside diameter of 
the pipe will give better results than two diam¬ 
eters. * 



















The Automobile Handbook 


19 


Admission-valves, Diameter and Lift of. 

For a motor of any desired bore and stroke, and ‘ 
speed in revolutions per minute, the following 
formula may be used to determine the diameter 
of the valve opening: 

Let B be the bore of the motor cylinder in 
inches, and S the stroke of the piston also in 
inches. As R is the number of revolutions per 
minute and D the required diameter of the 
valve opening, then 

B X S' X R 

D =- 

15,000 

Example: Required the diameter of the ad¬ 
mission-valve opening for a motor of 4L>-inch 
bore and stroke at 1,000 revolutions per minute. 

Answer: As 4f4 multiplied by 4X and by 
1,000 equals 20,250, then 20.250 divided by 15,- 
000 gives 1.35 inches as the diameter of the 
valve opening. 

In practice, a motor of 4% inches bore and 
stroke has, with a mechanically operated ad¬ 
mission-valve, an opening of 1 1 /> inches diame¬ 
ter and runs up to 1,200 revolutions per minute. 

The upper view in Figure 8 shows clearly the 
diameter D referred to in the formula, as some 
persons are in the habit of referring to the out¬ 
side diameter of the valve itself instead of the 
opening in the adniission-valve seat. The cen¬ 
ter view in Figure 8 shows an admission-valve 
with a flat seat, which is known as a mushroom 
valve, on account of its shape. For this form 



20 


The Automobile Handbook 


of valve to give a full opening the lift should 
he exactly one-fourth of the diameter of the 
valve opening: therefore if L be the required 
lift of the valve, and D the diameter of the 
valve opening, then 

D 

L = — = 0.25 D 
4 



Fig. 8 

The lower view in Figure 8 shows a valve 
with a bevel seat, having an angle of 45 degrees, 
which is most commonly used. The lift of this 
form of valve requires to be about three-eighths 
of the diameter of the valve opening; that is, if 
L is the required lift of the valve and D the 
diameter of the valve opening, then 













The Automobile Handbook 


21 


D 

L =-= 0.35 D 

2.83 

r l he bevel-seat form of valve is to be pre¬ 
ferred to the flat-seat or mushroom type of 
valve, for two reasons: first, that it is more 
readily kept in shape by regrinding, and sec¬ 
ond, it gives a freer and more direct passage 
for the gases, as will be plainly seen by refer¬ 
ence to the lower view in Figure 8. 

Table 1 gives the correct diameter of valve 
openings for motors from 3 by 3, to 6 by 6 inches 
bore and stroke, with speeds from 900 to 1,800 
revolutions per minute, and piston velocities of 
600, 750 and 900 feet per minute, for mechan¬ 
ically operated admission-valves. 


TABLE 1. 

DIAMETER OF MECHANICALLY OPERATED ADMISSION-VALVES. 


u 

o 


o 


o 

u 
' o 
K 


O 

o 

4 

41 

5 

7)h 

G 


c 

o 

Vl 

E 

O 

<U 

X 

o 

U 

-*-> 

U1 


9 1 
oa 


4 

4b 

5 


5i 

6 


Piston Speed in Feet per Minute 


600 


750 

900 

. per 
te. 

bi) 

O a,.5 

. per 

te. 


•M g 

° (0 B 

. per 
te. 

_ be 
o G 

V2 ^ 

> £ 

V. d 


> c 

m d 

. > £ 

> d 


> a 


cij~ K 

> c 

d-d 41 

0> -r-f 

•2 d ft 



•“sift 

<D -rH 

•2 d ft 


PP>0 

«§ 


p>o 

P5S 

Q>0 

1200 

0.72 

1500 


0.90 

1800 

1.08 

1030 

0.84 

1285 


1.05 

1570 

1.26 

900 

0.9G 

1125 


1.20 

1350 

1.44 

800 

1.08 

1000 


1.35 

1200 

1.62 

720 

1.20 

900 


1.50 

1080 

1.80 

655 

1.32 

820 


1.65 

965 

1.95 

GOO 

1.44 

750 

l 

1.80 

900 

2.16 


Atmospheric or suction operated admission- 
valves require to be of somewhat larger diame- 


























The Automobile Handbook 


9 2 

ter than mechanically operated admission- 
valves, for two reasons: first, that the incoming 
charge has to lift the valve from its seat and 
keep it suspended during the suction stroke of 
the motor piston, and secondly on account of 
the resistance offered by the valve spring, 
which tends at all times to keep the valve on its 
seat. For an atmospherically operated admis¬ 
sion-valve which will insure practically a full 
charge in the motor cylinder the formula 
should be 

B X S X R 

D =- 

12,750 

The proper diameter for atmospherically 
operated admission-valve openings may be 
readily found by increasing the required diam¬ 
eter given in the above table for mechanically 
operated admission-valves, by 15 per cent. 

Example: What should be the correct diam¬ 
eter for the atmospherically operated admis¬ 
sion-valve of a motor of 414 inches bore and 
stroke, with a piston velocity of 750 feet per 
minute ? 

Answer: Under the column headed 750 and 
opposite 4 1 /! by 4*4, the diameter given is 1.35. 
Then 15 per cent of 1.35 equals 0.20, which, 
added to 1.35, gives 1.55 inches as the correct 
diameter for the valve opening under the con¬ 
ditions given. 

Admission-valves, Forms of. Figures 9 and 
10 are two forms of combined admission-valve 



The Automobile Handbook 


23 



ADMISSION VALVE 

Fig. 9 



Fig. 10 


and valve cage or chamber. Figure 9 has the 
inlet on top and Figure 10 on the side. Figures 
11-12 show two forms of detachable or remov- 























































24 


The Automobile Handbook 



able admission-valves. The one shown in Fig¬ 
ure 12 may be removed from the motor without 
disconnecting the admission-pipe, as it screws 



ADMISSION VALVE 


Fig. 12 

into the combustion chamber, and has openings 
around the lower portion for the admission of 
the explosive charge to the valve. 
































The Automobile Handbook 


Air. Air consists, by weight, of oxygen 77 
parts and nitrogen 23 parts; by volume, of 21 
parts oxygen and 79 parts nitrogen. One pound 
of air at atmospheric pressure, and 70 degrees, 
Fahr., occupies 13.34 cubic feet of space. One 
cubic foot of air weighs 1 1-7 ounces. 


TABLE 2. 

PROPERTIES OF COMPRESSED AIR 


Comp, in 
Atmos¬ 
pheres. 

‘Mean 

Pressure. 

Temp, in 
Degrees 

Fah. 

S v 

‘Gauge 

Pres¬ 

sure. 

‘Absolute 

Pressure. 

‘Isother¬ 
mal Pres¬ 
sure. 

1 

0 

60 

0 

14.7 


3.68 

7.62 

145 

10 

24.7 

30.39 

2.02 

10.33 

178 

15 

29.7 

39.34 

2.36 

12.62 

207 

20 

34.7 

48.91 

2.70 | 

14.59 | 

234 

25 

39.7 

59.05 

3.04 

16.34 

252 

30 

44.7 

69.72 

3.38 

17.92 

281 

35 

49.7 

80.87 

3.72 | 

19.32 | 

302 

40 

54.7 

92.49 

4.06 

20.57 

324 

45 

59.7 

104.53 

4.40 

21.69 

339 

50 

64.7 

116.99 

4.74 

22.76 

357 

55 

69.7 

129.84 

5.08 

23.78 

375 

60 

74.7 

143.05 

5.42 

24.75 

389 

65 

79.7 

156.64 

5.76 

25.67 

405 

70 

84.7 

170.58 

6.10 

26.55 

420 

1 5 

89.7 

184.83 


*In pounds per square inch. 


Air Properties of Compressed. Table 2 gives 
the Mean pressure, Temperature in degrees 
Fahr., Gauge pressure, Absolute pressure and 
the Isothermal or heat pressure of air under 
compression of from 1 to 6.10 atmospheres. 

As energy in the form of power must be used 
to compress air to any desired pressure, so is 
energy in the form of latent or stored heat 
given up by the air during the operation of 
compression. This heat consequently increases 
the pressure resulting from the compression, 

















26 


The Automobile Handbook 


but not directly in proportion to the degree of 
compression in atmospheres. 

This increase of pressure above the Adiabatic 
or calculated pressure is known as the Isother¬ 
mal or heat-pressure. As the values of this 
pressure cannot be calculated by the use of 
ordinary mathematics, but involve the use of 
logarithms, Table 2 gives these values for each 
degree of compression given. 

Many persons who are not familiar with the 
properties of gases, estimate the pressure re¬ 
sulting from the compression to a given number 
of atmospheres, as the number of atmospheres 
multiplied by the atmospheric pressure, which 
at sea level is taken as 14.7 pounds per square 
inch. 

This assumption is erroneous and will often 
lead to grievous mistakes in motor design, 
generally giving too much compression, which 
results in premature ignition, commonly known 
as backfiring. Such methods of calculation 
would be true if the air, after compression, was 
stored in a reservoir and allowed to cool, but 
under no other conditions. 

Air-Cooled Automobile Engines. The suc¬ 
cessful air cooling of an engine cylinder de¬ 
pends chiefly on an abundant flow of cool air 
over it. Some cylinders, however, are arranged 
to utilize a more rapid flow than others. Gen¬ 
erally speaking, the designer can take his choice 
between a comparatively plain cylinder surface 
over which a current of air can flow almost un- 


The Automobile Handbook 


27 


checked, and a cylinder with its heat-radiating 
surface greatly multiplied by numerous pins, 
deep ribs, or other projections. These projec¬ 
tions increase greatly the radiating surface, but' 
tend to obstruct the flow of air, although they 
aid in carrying away the heat. In the latter 



case, the velocity of the air stream does not 
need to be high, provided it is continuous; while 
in the former case, a constant and abundant 
supply of air is essential. 

Air Cooling Systems. In modern automobile 
practice two systems of cooling are used—the 
air system and the water system, each of which 





















































28 


The Automobile Handbook 


has its adherents. As its name indicates, the 
air cooling system allows the air to strike the 
exterior of the engine cylinder, and thus carry 
off the excess of heat generated within it. To 
give the radiating surface, required for air 
cooling, the exteriors of the cylinders are either 


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Fig. 14 


grooved or corrugated, as shown in Fig. 13, 
or the surface of the cylinder is studded with 
metal pins or fins, as shown in Fig. 14, so as to 
present as much surface to the outside air as 
possible. The object in the construction of all 
air-cooled motors is to make their external sur¬ 
faces offer as great a surface to the air as pos- 































































































The Automobile Handbook 


29 


sibie, and to furnish these surfaces with as large 
a supply as possible. A fan is therefore used, 
driven by the engine itself, which constantly 
directs a current of fresh, unheated air upon 
the surface of the cylinder. 

Fig. 15 is a sectional view of a vertical air¬ 
cooled gasoline motor. The radiating ribs cast 
around the cylinder and valve chamber are 
plainly discernable. This motor has a detacha¬ 
ble atmospherically operated admission-valve, 
without packing. The valve and cage may be 
removed by simply removing two nuts. 

Air, Relation of to Gasoline. Owing to the 
fact that automobile gasoline is composed of 
various percentages of the several available 
fractions of hydrocarbon distillates, it is not 
possible to fix an exact basis for the relative 
proportions of air to fuel. However, the aver¬ 
age carbureter is capable of altering the ratio 
of air to fuel over broad ranges, and it is not 
necessary to know the exact ratio in order to 
attain the best results. But it is necessary to 
approximate an average ratio as nearly as pos¬ 
sible in designing and adjusting carbureters in 
order to allow for these variations up and 
down. 

The mixture becomes explosive when 10,000 
volumes of air dilute one volume of gasoline, 
but the best results follow when the ratio is 
one volume of liquid gasoline to 8,000 volumes 
of air. With one of gasoline to 3,500 of air the 
mixture is non-explosive. 


30 


The Automobile Handbook 

— 



AIR-COOLED MOTOR 


















































The Automobile Handbook 


31 


Air, Relation of in Gasoline Mixture. Gas¬ 
oline is a somewhat uncertain mechanical mix¬ 
ture of several hydrocarbon (fractional) distil¬ 
lates, in which the compound “hexane” is sup¬ 
posed to be the major portion. This compound 
answers to the formula C 6 II 14 , the products of 
combustion of which will be C 0 2 + C O -f- H 2 0, 
in which C O will not be found if the combus¬ 
tion is complete. A final expression of complete 
combustion will be as follows: 

2 C 0 H 14 X 19 0 2 = 12 C 0 2 + 14 H 2 0. 

Taking into account the atomic weight of the 
elements, the volume of air required in the com¬ 
plete combustion of 1 pound of hexane may be 
set down as follows—atomic weight of the ele¬ 


ments involved: 

Carbon (C). 12 

Hydrogen (II). 1 

Oxygen (0). 16 


The molecular weight of C„ II 14 = 6 X 12 + 
14X1 = 86; the required oxygen will weigh 
(molecular) 19 X 16 = 304; the ratio of the 
compound hexane, then, to the combining oxy¬ 
gen will be 

304 

Ratio =-= 3.54, nearly. 

86 

Considering 1 pound of hexane, the weight 
of oxygen required for its complete combustion 
will be equal to the ratio as above given, i.e., 
3.54 pounds, nearly. 

Since the oxygen is taken from the air, it is 






32 


The Automobile Handbook 


necessary to consider dry air in the attempt to 
determine as to the weight of the same. This 
air, under a pressure of 1 atmosphere, and at a 
temperature of 60 degrees Fahrenheit contains 
0.23 pounds of oxygen, hence the required air= 

3.54 

-- = 15.39, in pounds. 

.23 

Air Resistance, Horsepower Required to 
Overcome. The power required to move a plane 
surface, such as the vertical projection of an 
automobile, against the air, d.oes not become of 
much importance until the car attains a speed 
of 10 to 12 miles per hour, when it becomes an 
important factor. 

The horsepower required to propel an auto¬ 
mobile against the resistance of the air may be 
approximately calculated by the following for¬ 
mula. Let V be the velocity of the car in feet 
per second, and A the projected area of the 
front of the car in square feet—this may be as¬ 
sumed as the height from the frame to the top 
of the body multiplied by the width of the seat 
at the floor line of the car—let H.P. be the 
horsepower required to overcome the air re¬ 
sistance, then 

V 3 X A 

H.P.=- 

240,000 

To simplify the use of the above formula, 
Table 3 gives speeds in miles per hour corre- 




The Automobile Handbook 


33 


sponding to their respective velocities in feet 
per second and also cubes of velocities in feet 
per second. 


TABLE 3. 

CUBES OF VELOCITIES IN FEET PER SECOND. 


Miles per 
Hour of 
Car. 

Feet per 
Second. 

Cube of 
"V elocity 
in Ft. per 
Second. 


Miles per 
Hour of 
Car. 

Feet per 
Second, 

Cube of 
Velocity 
in Ft. per 
Second, 

10.2 

15 

3,375 

| 34.0 

50 

125.000 

13.6 

20 

8,000 

| 40.0 

60 

216,000 

17.2 

25 

15,625 

| 47.7 

70 

343,000 

20.4 

30 

27.000 

| 54.4 

80 

512,000 

27.2 

40 

64,000 

| 61.3 

90 

729,000 


To ascertain approximately the horsepower 
that will be necessary to drive a car against a 
wind of known velocity, the speed of the car 
must be added to that of the wind, and the re¬ 
quired horsepower may be found either by use 
of the formula given or by reference to Table 
4, which gives the horsepower per square foot 
of projected surface required to propel a car 
against the resistance of the air, with varying 
speeds in miles per hour or velocities in feet 
per minute. 

TABLE 4. 

HORSEPOWER REQUIRED PER SQUARE FOOT OF SURFACE, TO MOVE 
A CAR AGAINST AIR RESISTANCE. 


Miles per 
Hour of 
Car. 

Feet per 
Second. 

Horse¬ 
power per 
Square 
Foot of 
Surface. 

Miles per 
Hour of 
Car. 

Feet per 
Second. 

Horse¬ 
power per 
Square 
Foot of 
Surface. 

10 

14.7 

0.013 

40 


58.7 

0.84 

15 

22.0 

0.44 

50 


73.3 

1.64 

20 

24.6 

0.105 

60 


87.9 

2.83 

25 

36.7 

0.205 

80 


117.3 

6.72 

30 

44.0 

0.354 

100 


146.6 

13.12 


The horsepower given by the formula and 
Table 4 simply refers to the additional power 
































34 


The Automobile Handbook 


necessary to overcome air resistance and not to 
the actual power required to propel a car at a 
given speed; this is entirely another matter. 

Alcohol. There are two kinds of alcohol; 
methyl, or wood, alcohol, CH 4 0, and ethyl, or 
grain, alcohol, C 2 H 0 O. The former has been 
found objectionable for use in internal-combus¬ 
tion engines, because it apparently liberates 
acetic acid, which corrodes the cylinders and 
valves. 

As alcohol is a fixed product, and the same 
the world over, it lias a great advantage as a 
motive power over gasoline and other petro¬ 
leum products. Denatured alcohol contains 
4,172 heat units per pound as compared to 
18,000 for gasoline, and, as its cost is higher, 
this fuel would not seem practicable from an 
economic standpoint. By mixing the alcohol, 
however, with a high grade of gasoline, its price 
is lowered, and the number of heat units per 
pound greatly increased. Mixtures containing 
50 per cent 'alcohol have a calorific power of 
11,086 heat units per pound, and as it has been 
found by numerous tests in France that it re¬ 
quires no more of this mixture than of gasoline 
to develop a certain power, its efficiency is con¬ 
siderably greater, reaching a value of 24 per 
cent as compared to 16 for the gasoline motor. 
In some recent experiments in France with a 
motor specially constructed for the use of alco¬ 
hol, the consumption was lowered to 0.124 pound 


The Automobile Handbook 


35 


per horse power, using 50 per cent carburetted 
alcohol. 

Grain, or ethyl, alcohol has a specific gravity 
of .795, and may be obtained by distillation 
from corn, wheat, and other grains, potatoes, 
molasses, or anything containing sugar or 
starch. When pure, it absorbs water rapidly 
from the air, more rapidly in fact than it loses 
its own substance by evaporation; but when 
diluted to the proportion of about 85 per cent, 
alcohol and 15 per cent, water, it evaporates 
practically as if it were a single liquid and not 
a mixture. In France, it is denatured for mo¬ 
tor purposes by the addition of 10 liters of 90° 
wood alcohol, and 500 grams of heavy benzine, 
to 100 liters of 90° ethyl alcohol. In Germany, 
benzol is added to the extent of 15 per cent, for 
denaturing, no wood alcohol being used. In 
the United States the so-called “denatured” 
alcohol, which is that used in the arts and in¬ 
dustries, is composed of ethyl or grain alcohol, 
to which have been added certain diluents cal¬ 
culated to make it unfit for drinking. The In¬ 
ternal Revenue regulations specify that to 100 
volumes of ethyl alcohol there must be added 
10 volumes of methyl (wood) alcohol and one- 
half of one volume of benzine, or to the same 
quantity of ethyl alcohol must be added 2 vol¬ 
umes of wood alcohol and one-half of one vol¬ 
ume of pyridine bases. 

As compared with gasoline as a fuel for in- 


36 


The Automobile Handbook 


ternal-combustion motors, alcohol exhibits sev¬ 
eral striking peculiarities. 

First, the combustion is much more likely to 
be complete. A mixture of 90° alcohol vapor 
and air will burn completely Avhen the propor¬ 
tion varies from 1 of the vapor with 10 of air 
to 1 of the vapor with 25 of air, thus exhibiting 
a much wider range of proportions for combusti¬ 
bility than is the case with gasoline. As the 
combustion is complete, the exhaust is practi¬ 
cally odorless, consisting only of water vapor 
and carbon dioxide. 

Second, the inflammability of an alcohol mix¬ 
ture is much lower. This is due partly, no doubt, 
to the presence of water in the alcohol, which 
is vaporized with the alcohol in the engine and 
must be converted into steam at the expense of 
the combustion. 

For these reasons, the compression of an al¬ 
cohol mixture is carried far above that permis¬ 
sible with a gasoline mixture, without danger 
of spontaneous ignition. The rapidity of com¬ 
bustion of alcohol in an engine is considerably 
less than that of a gasoline mixture, and for this 
reason the speed of alcohol engines must be 
somewhat slow. 

The facts that alcohol of sufficient purity for 
use in engines can be produced from the waste 
products of many of the country’s industries, 
and at a nominal cost, and that many thousands 
of acres of land, unfit for the cultivation of 
first-class grain, etc., may be utilized for the 


The Automobile Handbook 


37 


production of vegetable matter rich in the ele¬ 
ments which form alcohol upon fermentation, 
lead to the supposition that within a few years, 
or as soon as there is a sufficient demand for 
alcohol to warrant the erection of special dis¬ 
tilleries, it may be purchased at such a low price 
that it will not only be commercially possible, 
but will in a measure force gasoline and other 
petroleum distillates from the field. 

A carbureter designed to operate with alcohol 
can always be used with gasoline, but the re¬ 
verse conditions are not true, that is, a gasoline 
carbureter will not operate successfully with 
alcohol, except in some rare instances. Alcohol 
evaporates slower than gasoline and its time of 
combustion is much slower, but it maintains its 
mean effective explosion pressure far better 
than gasoline. 

Explosive motors fitted with alcohol carbu¬ 
reters make far less noise than when using gaso¬ 
line as a fuel, due to the slower burning of the 
explosive charge, they also make less smoke 
and smell. 

The jet or spray of a float-feed carbureter will 
have to pass nearly 40 per cent, more liquid 
fuel than when using gasoline, consequently the 
opening in the nozzle must be proportionally 
larger. 

A carbureter using alcohol must be fitted with 
some form of device to heat the alcohol to en¬ 
sure rapid evaporation—this is usually done by 


38 


The Automobile Handbook 


surrounding the mixing-chamber with an ex¬ 
haust-heated jacket. 

The same quantity of alcohol will only take 
a car two-thirds of the distance that gasoline 
will, hence greater storage capacity would be 
needed on a car using alcohol as a fuel. 

An explosive motor designed to use alcohol 
requires a greater degree of compression than a 
motor of the same bore and stroke designed to 
use gasoline, in order to develop the same 
power. 

Alternating Current, Use of. It is not only 
useless but absolutely injurious to attempt to 
charge a storage battery directly from an alter¬ 
nating current circuit. This can only be done 
by means of a rotary converter, which is in 
reality a motor-generator, receiving its power 
from the alternating current and transforming 
it into a direct current which can be used to 
charge the batteries. 

Aluminum. A soft ductile malleable metal, 
of a white color, approaching silver, but with a 
bluish cast. Very non-corrosive. Tenacity 
about one-third that of wrought iron. Specific 
gravity 2.6. Atomic weight 27.1. It is the 
lightest of all the useful metals, with the excep¬ 
tion of magnesium. 

Aluminoid, Composition and Use of. A In¬ 
in inoid is composed by weight of 60 parts alu¬ 
minum, 30 parts tin and 10 parts zinc. It has a 
tensile strength of about 18,000 pounds and is a 
very suitable material for cmnk chambers, gear 


The Automobile Handbook 39 

cases and small brackets, being light, extremely 
ductile and readily machined. 

Aluminum Solder. The following formula is 
for a solder which will work equally well with 
aluminum or aluminoid: Tin, 10 parts—cad¬ 
mium, 10 parts—zinc, 10 parts—lead, 1 part. 
The pieces to be soldered must be thoroughly 
cleansed and then put in a bath of a strong solu¬ 
tion of hyposulphate of soda for about two 
hours before soldering. 

Alloys, Composition of. The proper compo¬ 
sition of alloys of metals for the bearings and 
other parts of an automobile is a very important 
consideration from a constructive standpoint. 
Table 5 gives the composition of various alloys 
of metals and also solders for different uses. 

TABLE 5. 

COMPOSITION' OF AI.I.OVS. 











r* 


& 




o 


-4-» 




£ 


d 


a 

d 



£ 

£ 

a 

o 

c 

4-> 

£ 

d 

<u 



V 

N 

<< 


5 

13 

110| 

1 




25 

160| 

5 





O 1 

i 





32] 

i 


1 


10 

1 | 

• • • 

i 



16 

130| 

i 

9 

0 

i 

2 

901 

5 


2 


I 

1 1 

1 


2 


i 

4 1 

3 





Bronze, for Motor bearings. 

Bronze, for Axle bearings. 

Brass, for light work, other than 

hearings . 

Bronze flanges, to stand brazing. . . 

Genuine Babbitt metal. 

Bronze, for bushings . 

Metal to expand in cooling, for 

patterns . 

Genuine bronze . 

Solder, for tin . 

Spelter, hard... 

Spelter, soft .. 


American Locomotive Carbureter. The float 

feed carbureter used on this car is automatic in 
regulating the admission of mixture to the cyl- 





































40 


The Automobile Handbook 


inders. The air is heated on its way to the car¬ 
bureter, and a bypass operated by hand from 
the dash adjusts the mixture to varying atmos¬ 
pheric conditions. 

Ammeter, Construction of. Ammeters for 
automobile use are constructed on the principle 



Fig. 16 

* o 

of the D'Arsonval galvanometer with a perma¬ 
nent magnetic field. The special feature is a 
small oscillating coil mounted on cone-point 
bearings surrounding a stationary armature 
which is -centrally located between the pole- 
pieces of a permanent magnet, with a pointer 
or index-finger which indicates the electrical 
variations on a graduated scale. 












































The Automobile Handbook 


41 


The construction of an ammeter is fully 
show in the two views in Figure 16. The per¬ 
manent magnets used in its construction are of 
a special quality of hardened steel, made only 
for this purpose and possessed of great mag¬ 
netic permeability. The pole-pieces, which are 
of soft steel and well annealed, are attached to 
the inside of the lower part of the magnet legs, 
the joints between the pole pieces and the mag¬ 



net legs are usually ground to insure the full 
efficiency of the magnetic circuit. The soft iron 
core of the coil is for the purpose of rendering 
uniform the magnetic field in which the coil 
must oscillate. A coil of insulated wire is 
wound upon the stationary armature at right 
angles to its axis, in the same manner that 
thread is wound upon a spool, and is short-cir¬ 
cuited on itself, that is to say, the ends of the 
wire forming the coil are connected together. 
This coil of wire is for the purpose of choking 

























42 


The Automobile Handbook 


the magnetism induced in the stationary arma¬ 
ture by the oscillating coil, as it generates what 
are known as eddy currents within itself, thus 
making the instrument periodic, or dead-beat, 
in its indications. Around the armature core 
and outside the short-circuited coil of wire is 
wound the active or oscillating coil and at right 
angles to the direction of the winding of the 
first coil. The oscillating coil consists of a num¬ 
ber of turns of fine insulated copper wire, to 
which the current is conveyed through the me¬ 
dium of the controlling springs at each end of 
the spindle, which is in two parts and con¬ 
nected together by a suitable sleeve of insulat¬ 
ing material, as shown. 

The pointer or index-finger is made with a 
boss or hub to go over the end of the spindle of 
the active coil and also has an extension with a 
small counterweight or balance, so that the’ 
pointer may be accurately adjusted. 

The onlv difference in the construction of a 

•/ 

voltmeter and an ammeter is that in the former 
the active or oscillating coil is in series with a 
high resistance, while in the latter it is con¬ 
nected across the terminals of a shunt-block. 
The voltmeter is in reality an ammeter, the re¬ 
sistance serving to keep the amperage in step 
•with the voltage. 

Reference to the three views, marked re¬ 
spectively A, B and C in Figure 17, will show 
clearly the principle of the operation of an 
ammeter or voltmeter, and the reason that they 


The Automobile Handbook 


43 


record the current strength or pressure of an 
electric current accurately. 

Ammeters are of two kinds, the double-beat 
type, as shown in Figure 16, which indicates the 
current strength or number of amperes flowing 
in the electric circuit, without any regard to 
the polarity of the terminals of the circuit, by 
the pointer or index-finger moving either to the 
right or to the left of the zero position. The 



single-beat type of ammeter only records in 
one direction, by the pointer moving from the 
left to the right of the graduated scale of the 
instrument, consequently the polarity of the 
terminals of this type of ammeter are marked 
on its outer casing and the polarity of the ter¬ 
minals of the electric circuit must consequently 
be determined before connecting them with the 
ammeter. 




















44 


The Automobile Handbook 


A volt-ammeter, such as is commonly used on 
electric automobiles, is shown in Figure 18. 
This instrument is simply a voltmeter and a 
double-beat ammeter mounted on a single base 
and enclosed in a common case, with their 
graduated scales adjoining each other. 

Ampere. The unit of electric current flow. 
An ampere is that volume of current which 
would pass through a circuit that offered a re¬ 
sistance of one ohm, under an electromotive 
force of one volt. 

Ampere-hour, Definition of. The term am¬ 
pere-hour is used to denote the capacity of a 
storage or a closed-circuit primary battery for 
current. A storage battery that will keep a 2 
ampere lamp burning for 8 hours is said to 
have a 16 ampere-hour capacity. In a similar 
manner an 80 ampere-hour battery would ope¬ 
rate the same lamp 40 hours. The voltage of a 
battery does not enter into the calculation of 
its ampere-hour capacity. 

Anchoring Top Irons. Cape cart hood irons 
are sometimes attached to the front seat as 
illustrated in Fig. 22, which indicates the ap¬ 
pearance inside the arm of the front seat with 
the upholstery stripped away. The lower end 
of the iron goes through the overhanging part 
of the seat and the nut, A, is on the outside. 
The iron is steadied by an ordinary wood screw, 
B, which goes into the framing of the arm. If 
the iron is curved as the sketch shows, there is 
a considerable leverage on B, tending to break 


The Automobile Handbook 


45 


it off. If it breaks the free movement of the 
arm tears the upholstery. A permanent job 
can be made by drilling the hole through which 
B passes and putting in a slightly larger screw, 
C, and also putting on a strap, D, beneath it. 
This strap, D, then does the greater part of the 
work, and has the effect of causing any twist 
applied to the iron to be held by the screw, C, 



Fig. 19 

Annular Ball Bearing 

where it enters the wood, insead of exerting a 
leverage against it just under the head. 

Angle Iron. A bar of iron rolled into the 
shape of the letter L, or V. 

Annular Ball Bearings. In the annular ball 
bearing, Fig. 19? a race of balls C is contained 
between an inner retainer A and an outer race 
B, there being grooves in the opposing surfaces 
of these to receive the balls. In a Hess-Bright 





46 


The Automobile Handbook 


bearing of this type, as illustrated in Fig. 20, 
the entire space between the races C and B is 
not occupied by balls, but is utilized in different 
ways. In this only enough balls to make a half 
circle in the bearing are used, and these are 
spaced apart by means of small helical springs. 
These springs contain oil pads of felt, and are 
headed by sheet-metal discs that extend far 



Fig. 20 

Hess-Bright Bearing 

O o 


enough into the grooves to prevent sidewise dis¬ 
placement of the springs, without, however, 
producing any more than a negligible friction. 
Assembling this bearing one race is placed ec¬ 
centric to another race and the requisite num¬ 
ber of balls slipped into positions, after which 
the races are made concentric and the balls reg¬ 
ularly distributed. This done, the separating 
springs with lubricating means are installed. 



The Automobile Handbook 


47 


Once the springs are in place the tension of them 
is such as to make the bearing self-contained. 

Annoying Squeaks, Remedy for. A squeak 
that is caused by the edge of a door rubbing 
against its pillars may be remedied as shown 



in Fig. 23. This rubbing, generally occurring at 
A, Fig. 23, is brought about by a sagging of 
the body in the center, and may be remedied by 
placing a leather washer of the required thick¬ 
ness around the body bolt, between the body 





































48 


The Automobile Handbook 


and the frame at B. This sagging may be due 
to a sagging of the frame, in which case the 
motor and change-gear case may also require a 
little lining up. Body squeaks of the same 
nature occasionally occur at C, or at D when 
the body is jointed to the dash at D, and for 
the same reasons as above stated. Another cause 
is due to negligence on the part of repair men 
to replace one or two of the washers originally 



Fig. 22 

Anchoring Cape Cart Hood Irons 


provided, after a body has been removed for re¬ 
pairs; the washers being more apt to stick to 
the body when it is removed, and drop off unno¬ 
ticed before same is replaced. 

Anti-Freezing Mixtures. If a solution of al¬ 
cohol and water is used, the best results will be 
obtained by having it just strong enough to 
stand the lowest temperature to which it is 
likely to be subjected in the climate where it 
is to be used. 



















The Automobile Handbook 


49 


The reason for this is that the alcohol evapo¬ 
rates out from the solution, and the stronger the 
solution, the more there is to evaporate, the 
easier it evaporates, and the greater the influ¬ 



ence of this evaporation upon the solution left. 

The diagram shown in Fig. 21 indicates the 
freezing points of various solutions of dena¬ 
tured alcohol, also of wood alcohol. From this 
diagram a solution may be selected which will 


















50 


The Automobile Handbook 


stand any temperature from 50° below zero to 
40° above. 

Other solutions may be made with calcium 
chloride (common salt), also the salts known as 
potassium carbonate. These with water form a 
solution that will stand zero temperatures, but 
are not available where lower temperatures are 
common. 

Aprons. The vital parts of an automobile 
mechanism, particularly the engine and the 
change speed gear, are protected by some sort 
of pan or apron under the car. In most cities 
aprons are required by law, in order to prevent 
the surplus oil from dropping on the pavement 
under the car. Leather and canvas aprons have 
been used in the past, but they have been largely 
superseded by sheet metal aprons. Most of 
these metal pans are simply thin sheet steel or 
aluminum, riveted or otherwise attached to the 
side sills. In a few instances, however, the steel 
pan is made to constitute a web, integral with 
the side sills, and made, of course, of the same 
piece of sheet steel stock. 


'The Automobile Handbook 


51 


TABLE 6. 

AREAS AND CIRCUMFERENCES OF CIRCLES FROM 0.05 TO 10.0, 
ADVANCING BY ^ OF ONE INCH. 


I >iam. 

Area 

Circurn 

.05 

.0010 

.10 

.10 

.0078 

.31 

.15 

.017 

.47 

.‘JO 

.031 

.63 

. J5 

.040 

.78 

.30 

.070 

.04 

.35 

.006 

1.09 

.40 

.12 

1.26 

.45 

.16 

1.41 

.50 

.19 

1.57 

.55 

.24 

1.73 

.00 

.28 

1.88 

.65 

.33 

2.04 

.70 

.38 

2.19 

.75 

.44 

2.36 

.80 

.50 

2.51 

.85 

.57 

2.67 

.00 

.64 

2.83 

.95 

.71 

2.98 

1.00 

.78 

3.14 

1.05 

.86 

3.29 

1,10 

.95 

3.46 

1.15 

1.03 

3.61 

1.20 

1.13 

3.77 

1.25 

1.23 

3.93 

1.30 

1.33 

4.08 

1.35 

1.43 

4.24 

1.40 

1.54 

4.39 

1.45 

1.65 

4.56 

1.50 

1.77 

4.71 

1.55 

1.89 

4.87 

1.00 

2.01 

5.03 

1.05 

2.14 

5.18 

1.70 

2.27 

5.34 

1.75 

2.40 

5.49 

1.80 

2.54 

5.65 

1.85 

2.69 

5.81 

1.00 

2.84 

5.97 

1.05 

2.99 

6.13 

2.00 

3.14 

0.28 


I 


Diam. 

Area 

Circum. 

2.05 

3.30 

6.44 

2.10 

3.46 

6.59 

2.15 

3.63 

6.75 

2.20 

3.80 

6.91 

2.25 

3.98 

7.07 

2.30 

4.15 

7.22 

2.S5 

4.34 

7.38 

2.40 

4.52 

7.54 

2.45 

4.71 

7.69 

2.50 

4.91 

7.85 

2.55 

5.11 

8.01 

2.60 

5.31 

8.17 

2.65 

5.56 

8.32 

2.70 

5.72 

8.48 

2.75 

5.94 

8.64 

2.80 

6.16 

8.79 

2.85 

6.38 

8.95 

2.90 

6.60 

9.11 

2.95 

6.83 

9.27 

3.00 

7.07 

9.42 

3.05 

7.31 

9.58 

3.10 

7.55 

9.74 

3.15 

7.79 

9.89 

3.20 

8.04 

10.05 

3.25 

8.29 

10.21 

3.30 

8.55 

10.37 

3.35 

8.81 

10.52 

3.40 

9.08 

10.68 

3.45 

9.35 

10.84 

3.50 

9.62 

10.99 

3.55 

9.89 

11.15 

3.60 

10.18 

11.31 

3.65 

10.46 

11.47 

3.70 

10.75 

11.62 

3.75 

11.04 

11.78 

3.80 

11.34 

11.94 

3.85 

11.64 

12.09 

3.90 

11.94 

12.25 

3.95 

12.25 

12.41 

4.00 

12.57 

12.57 





















52 


The Automobile Handbook 


TABLE 6—Continued. 


Diana. 

Area 

Cireum 

4.05 

12.88 

12.72 

4.10 

13.20 

12.88 

4.15 

13.53 

13.04 

4.20 

13.85 

13.19 

4.25 

14.19 

13.35 

4.50 

14.52 

13.51 

4.55 

14.86 

13.66 

4.40 

15.20 

13.82 

4.45 

15.55 

13.98 

4.50 

15.90 

14.14 

4.55 

16.25 

14.29 

4.00 

16.62 

14.45 

4.65 

16.98 

14.61 

4.70 

17.35 

14.76 

4.75 

17.73 

14.92 

4.80 

18.09 

15.08 

4.85 

18.47 

15.24 

4.90 

IS. 86 

15.39 

4.95 

19.24 

15.55 

5.00 

19.63 

15.71 

5.05 

20.03 

15.86 

5.10 

20.43 

16.02 

5.15 

* 20.84 

16.18 

5.20 

21.23 

16.34 

5.25 

21.65 

16.49 

5.30 

22.06 

16.65 

5.35 

22.48 

16.81 

5.40 

22.90 

16.96 

5.45 

23.33 

17.12 

5.50 

23.76 

17.28 

5.55 

24.19 

17.44 

5.60 

24.63 

1 7.59 

5.65 

25.07 

17.75 

5.70 

25.52 

17.91 

5.75 

25.97 

1 S.06 

5.80 

26.42 

18.22 

5.85 

26.88 

18.38 

5.90 

27.34 

18.54 

5.95 

27.80 

18.69 

6.00 

28.27 

18.85 

6.05 

28.75 

19.01 

6.10 

29 22 

19.16 

6.15 

29.70 

19.32 

6.20 

30.19 

19.48 


Diana. 

Area 

Cireum. 

6.25 

30.68 

19.63 

6.30 

31.17 

19.79 

6.35 

31.67 

19.95 

6.40 

32.17 

20.11 

6.45 

32.67 

20.26 

6.50 

33.18 

20.42 

6.55 

33.69 

20.58 

6.60 

34.21 

20.73 

6.65 

34.73 

20.89 

6.70 

35.26 

21.05 

6.75 

35.78 

21.20 

6.80 

36.32 

21.36 

6.85 

36.85 

21.52 

6.90 

37.39 

21.68 

6.95 

37.94 

21.83 

7.00 

38.48 

21.99 

7.05 

39.04 

22.15 

7.10 

39.59 

22.30 

7.15 

40.15 

22.46 

7.20 

40.71 

22.62 

7.25 

41.28 

22.78 

7.30 

41.85 

22.93 

7.35 

42.43 

23.09 

7.40 

43.01 

23.25 

7.45 

43.59 

23.40 

7.50 

44.18 

23.56 

7.55 

44.77 

23.72 

7.60 

45.36 

23.88 

7.65 

45.96 

24.03 

7.70 

46.57 

24.19 

I 7.75 

47.17 

24.35 

7.80 

47.78 

24.50 

7.85 

48.39 

24.66 

7.90 

49.02 

24.82 

7.95 

49.64 

24.97 

8.00 

50.26 

25.13 

8.05 

50.89 

25.29 

8.10 

51.53 

25.43 

8.15 

52.17 

25.60 

8.20 

52.81 

25.76 

8.25 

53.46 

25.92 

8.30 

54.11 

26.07 

8.35 

54.76 

26.23 

8.40 

55.42 

26.39 






















The Automobile Handbook 


53 


TABLE 6—Continued. 


Diarn. 

Area 

Circum. 

Diarn. 

Area 

Circum. 

8.45 

56.08 

26.55 


9.25 

67.20 

29.06 

8.50 

56.74 

26.70 


9.30 

67.93 

29 22 

8.55 

57.41 

26.86 


9.35 

68.66 

29.37 

S.60 

58.09 

27.02 


9.40 

69.39 

29.53 

8.65 

58.76 

27.17 


9.45 

70.14 

29.69 

8.70 

59.45 

27.33 | 


9.50 

70.88 

29.84 

8.75 

60.13 

27.49 


9.55 

71.63 

30.00 

8.80 

60.82 

27.65 | 


9.60 

72.38 

30.15 

8.85 

61.51 

27. SO | 


9.65 

73.14 

30.32 

8.90 

62.21 

27.96 | 


9.70 

73.89 

30.47 

8.95 

62.91 

28.12 


9.75 

74.66 

30.63 

9.00 

63.62 

28.27 


9.80 

75.43 

30.79 

9.05 

64.33 

28.43 | 


9.85 

76.20 

30.94 

9.10 

65.04 

28.59 1 


9.90 

76.98 

31.10 

9.15 

65.76 

28.74 


9.95 

77.76 

31.26 

9.20 

66.48 

28.90 


10.00 

78.56 

31.42 



Fig. 24 

Armatures, Slotted and Shuttle Types of. 

An armature is the rotating part of a dynamo 
or electric motor which generates electricity or 
develops power. 


















54 


The Automobile Handbook 


/ 


The armature shown at top of Figure 24 is 
known as the Siemen’s H or shuttle type and is 
the simplest form of wire-wound armature 
known. The current given by this form of 
armature is of the alternating type and is con¬ 
verted into a direct-current, when desired, by 
means of a two-part commutator on the arma¬ 
ture shaft. 

The slotted type of armature shown at the 
bottom of Figure 24 has a more intricate sys¬ 
tem of winding than the shuttle type just de¬ 
scribed. It has, however, a far greater elec¬ 
trical efficiency and gives off a steadier current 
than the shuttle type. It is the form most gen¬ 
erally used for automobile and street railway 
motors. Like the shuttle type of armature, the 
current generated by the slotted type of arma¬ 
ture is alternating, and is converted into a di¬ 
rect current by means of a commutator of very 
complicated form. 

Asbestos. Asbestos is principally a hydrous 
silicate of magnesia, that is, silicate of magnesia 
combined with water. When harsh fibre is an¬ 
alyzed it is found to contain less water than 
the soft fibre. If soft fibre be heated to a tem¬ 
perature which will evaporate a portion of the 
combined water, there results a substance so 
brittle that it may be crumbled between the 
thumb and finger. 

There is evidently some connection between 
the consistency of the fibre, and the amount of 
water in its composition. 


The Automobile Handbook 


55 


Assembling* a Car. In assembling the car the 
engine had best be put together first. When 
putting the pistons in their respective cylinders 
see that the splits or joints in the piston rings 
are not in line, but are spaced evenly around 
the piston. See that all parts are thoroughly 
clean and that no grit, or stray strands of waste 
happen to be caught on any projection. All 
nuts and bolts should be screwed tight and the 
jaws of the wrench should be properly adjusted 
to them, that the corners of the nuts and j?ap 
screws may not be rounded off. Insert the cot¬ 
ter pin after each nut has been screwed home. 
In joints where packing is required the old 
packing may be used if it is in good shape. 
Joint faces should, of course, be perfectly clean. 
A stout grade of manila wrapping paper soaked 
in linseed oil will make an excellent packing for 
crankcase and other joints having a good con¬ 
tact surface. 

While the engine is being reassembled it will 
be found advantageous to check up the valve 
timing. To do this, turn the fly-wheel until 
the inlet valve plunger of No. 1 cylinder just 
touches the lower end of its valve stem. At this 
point the line on the fly-wheel indicating “ Inlet 
No. 1 Open” should coincide with the pointer 
on the engine base. If the contact between the 
valve stem and the plunger is made before the 
mark on the fly-wheel lines up w T ith the pointer, 
the valve opens too early. In most cars the 
adjustments may be made by the screw cap and 


56 


The Automobile Handbook 


lock-nut on the plunger. As the valve stems are 
lowered by repeated grindings of the valves, 
the plungers require adjustment occasionally 
to compensate for this movement. Insert a 
piece of paper between plunger and valve stem, 
and by lightly pulling on the paper the time of 
contact and the moment of release may be de¬ 
termined to a nicety. When the paper is held 
tightly, a good contact is assured, and the mo¬ 
ment the paper becomes loose and can be moved 
about, the contact is broken. In many cars the 
reference or index mark on the engine bed is 
omitted; in this case the markings on the fly¬ 
wheel must be brought directly to the top. The 
other inlets and the exhaust valves should then 
be similarly checked up and adjusted. 

Most cars base the valve setting on a 1-32 
inch clearance space between valve stem and 
plunger rod when the valve is closed. This 
may be taken as the minimum amount, and 
should not be increased. A larger amount of 
clearance will cause the exhaust valve to open 
too late, and, the exploded gases not being en¬ 
tirely expelled, the power of the motor will be 
impaired. This clearance is necessary to allow 
for the expansion of the valve stem when it be¬ 
comes heated. 

Too much stress cannot be laid on the neces¬ 
sity of going about the work in an orderly and 
methodical manner. A mechanic who leaves 
parts lying about carelessly will rarely be found 
a good one, and certainly he is not a proper 


The Automobile Handbook 


57 


model for the amateur to copy. With the proper 
circumspection, then, and with a little ‘'horse 
sense” in applying the directions to his par¬ 
ticular make of car, the amateur owner should 
have no difficulty in making a good job of over- 



Atwater-Kent Spark Generator 

hauling, thus bettering the condition of his ma¬ 
chine and at the same time acquiring a valua¬ 
ble stock of knowledge for the future. 

Atwater-Kent Spark Generator. This device 
is designed to draw from a battery, as nearly as 
possible, only the electrical energy necessary 



























































58 


The Automobile Handbook 


to ignite the charge, and to keep the batteries 
until the energy remaining in them is too small 
to produce an effective spark. Its principal 
constituent parts are, a jump-spark coil and 
condenser, a primary contact maker, the time 
of which may be advanced or retarded, and a 
high tension distributer. Its distinguishing 
features are—* 

a. But one spark is made for each ignition. 

b. The primary contact, rupture of which 
produces the spark, is exceedingly brief, no 
longer in fact than is actually required to build 
up the magnetism in the core of the spark coil. 

c. The duration of this contact is independ¬ 
ent of the engine speed in the same way that 

t 

the contact of the ordinary coil vibrator is. 

d. Contact is made and broken mechanically 
through a shaft driven by the engine, conse¬ 
quently a spark may be obtained from a bat¬ 
tery that is too weak to operate a vibrator. The 
mechanism by which the instantaneous primary 
contact is produced is similar to a snap contact 
produced by a small spring-controlled hammer 
pulled out of position by a ratchet on the shaft. 
The ratchet has as many teeth as there are cvl- 
inders, and runs at the camshaft speed. When 
used with a two-cycle engine, it runs at the 
crankshaft speed if there are four cylinders. If 
there are two cylinders, it runs at half the en¬ 
gine speed and the ratchet has four teeth. The 
ordinary commutator is not used in connection 
with it, but a driving connection must be made 


The Automobile Handbook 


59 


from the crankshaft or camshaft to the vertical 
shaft of the spark generator itself, which is 
mounted on the back of the dashboard. 

The different parts of the Atwater-Kent 
spark generator are shown in Fig. 25, in which 
A is a cover on contact maker; B, starting but¬ 
ton for starting engine on spark; C, wing nut 
for holding cover on contact maker; D, dis¬ 
tributer; E, distributer blade (there are four 



of these, only one being lettered) ; F, secondary 
brush holder (inside this brush holder is a 
brush, bearing by spring tension against dis¬ 
tributer) ; G, distributer board; IT, H, H, IT, 
secondary binding-posts; I, I, I, I, cylinder cut¬ 
outs ; J, spark advancing mechanism; Iv, spark 
advancing shaft; L, driving shaft; M, switch; 
N, switch plug; 0, switch handle; P, carbon 
battery binding-post; Q, Q, holes for bolts to 
Void spark generator on dash (two of these on 
















60 


The Automobile Handbook 


other side are not shown) ; R, oil tube; S, 
clamping collar for setting time of spark; T, oil 
cup. 

The essential feature of the Atwater-Kent 
generator is the contact maker shown in Figs. 
26-27. 

The plan is show in Fig. 26, where the follow¬ 
ing moving parts are shown: A, the shaft; B, 
rhe snapper, and C, the pivoted contact arm. 
The shaft is provided with four milled notches 



Atwater Kent Contact Maker 

. v or six fcr a six-cylinder engine), forming a 
ratchet which engages the claw at the end of 
the snapper. This latter is a light, tempered 
steel piece which is guided by slots in the bronze 
base E D, and held against a stop G made of 
spring wire by means of a spring F, when re¬ 
leased from engagement with the notches on 
the shaft. Contact arm C is also held normally 
in the position shown by the tension of the coil 
spring If. 

The shaft, turning m a counter-clockwise di¬ 
rection, draws the snapper into position, the 













The A u tomobile Handbook 


61 


claw of the snapper when released riding up on 
the rounded part of the shaft, Fig. 27, thus act¬ 
ing as a wedge between the shaft and the steel 
hook I of the contact arm which is pivoted at 
J. The contact arm is thus oscillated to pro¬ 
duce contact between a platinum point on a 
flat copper spring K, and the insulated station¬ 
ary contact screw L. As the snapper continues 
its motion it releases I, permitting the contact 
arm to rebound and break contact. The snap¬ 
per comes to rest in its normal position as in 
Fig. 26, and the contact arm resumes its posi¬ 
tion resting against the stop. The operation 
is repeated when the snapper engages the next 
tooth of the ratchet. 

Autogenous Welding. This process consists 
of welding, or, more correctly speaking, melt¬ 
ing together metals by means of the oxyacety- 
lene flame, the temperature of which almost 
rivals that of the electric arc, being 6,300 de¬ 
grees Fahrenheit. The facility with which it 
can be handled as compared with most other 
methods makes its commercial application com¬ 
paratively simple. The possibilities attendant 
upon the use of a flame of such high tempera¬ 
ture can be realized when it is remembered that 
the melting point of steel is about 2,570 degrees 
and that of platinum, one of the most refrac¬ 
tory metals, is only 3,227 degrees Fahrenheit. 
Its chief field of usefulness is in combining such 
metal parts as would ordinarily be riveted, in 
welding small parts together, in repairing bro- 


62 


The Automobile Handbook 


ken or defective castings and for cutting metals 
of any nature or size that occasions demand. 

As it is possible to unite many dissimilar 
metals, and with a heat so localized that neigh- . 
boring parts are not affected, autogenous weld- 


00 

<N 


00 

• 


ing has already found an extensive application 
in motor car repair work. Broken crankcases 
or other parts can be united and made practi¬ 
cally as strong as new. The method of holding 
the pieces of a broken aluminum case, for exam- 



































The Automobile Handbook 


63 


pie, is to clamp them into position temporarily 
while clay is packed around the parts and 
heated sufficiently to drive out the moisture, 



Fig. 28a 
Auto-Meter 


thus forming a solid support for the parts as 
well as a kind of mould. A series of holes are 
usually drilled at the crack, or the edges of the 









64 


The Automobile Handbook 


pieces are roughly beveled so, as previously ex¬ 
plained, the metal can be built up from the bot¬ 
tom. In some instances lugs or peculiar shaped 
projections may have been completely worn off 
or destroyed when it becomes necessary to build 
up new ones with additional metal. In repair¬ 
ing a cracked water jacket, after the edges of 
the crack have been prepared, it is customary 
to use copper instead of iron wire for the filling 
metal as it flows at a lower temperature and 
-adheres very positively. In case there is dan¬ 
ger of warping, due to local expansion, the 
entire cylinder is heated before operating 
upon it. 

Auto-Meter. Figures 28a and 28b show an 
outside view and a cross-section of the Auto- 
Meter which illustrates its internal mechanism. 
0 is the magnet which revolves freely on ball 
bearings. It is not connected in any way with 
the indicating dial. The latter is suspended in 
front of the magnet and a partition separates 
them, precluding the possibility of air affecting 
it. The dial is mounted on a pivot, the ends of 
which ride in sapphire bearings. The pivot 
ends are carefully ground and lapped with dia¬ 
mond dust. 

The hair spring H holds the dial to zero point. 
The magnet when revolving has a tendency to 
draw the dial in the direction of its revolution. 
The hair spring opposes this tendency. The 
greater the rapidity of the magnet’s revolution, 
the greater the displacement of the dial, and 


The Automobile Handbook 


65 


r 



Fig. 28b 


Cross-Section of Auto-Meter 

when the speed of the magnet doubles, the dis¬ 
placement is doubled. In a word, the displace¬ 
ment increases proportionately as the speed 
increases, so that even reading over the entire 



















66 


The Automobile Handbook 


scale results. The length of the dial is prac¬ 
tically six inches. The action of the magnet on 
the dial being direct there is nothing interven¬ 
ing to cause a variation in its reading. 

The worm, driven by the same shaft that 
drives the magnet C, operates the worm gear 
which is connected directly to the odometer. 
This odometer can be removed in a moment, if 
necessary. 

Driving the odometer, as above described, 
obviates the danger of knocking it off, which is 
likely to occur were it mounted on the axle. 
Mounted on the dashboard where it can be 
tilted to any angle to accommodate the vision of 
the motorist, it is possible for him to determine 
the distance covered at any stage of the jour- 
ney. 

The magnet is so shaped that it will not weak¬ 
en and affect the reading ot‘ the instrument. 

The internal parts of the Auto-Meter are 
gold plated. This is not done to please the eye 
of the user, for he never sets eye on these parts, 
but to add to their durability. It is a contribu¬ 
tion to cleanliness and a preventive of corrosion. 
The ball cups and cones are carefully made from 
the best steel and thoroughly tested before 
used. To make assurance doubly sure, the 
instrument is tightly sealed and becomes ab¬ 
solutely dustproof. 

The instrument will show accurately a speed 
of one mile per hour and many an automobile 
owner has been surprised to learn that his aver- 


The Automobile Handbook 


67 


Fig. 29 

Typical American Gasoline and Electric Automobiles 
See Automobiles, Typical American 


























































































































68 


The Automobile Handbook 


age speed while traveling through the city 
streets has been from fifteen to twenty-five 
miles per hour. 

Automobile. A self moving vehicle, espe¬ 
cially a carriage driven by steam, gasoline, elec¬ 
tric, or other power, by means of a motor borne 
on the vehicle. 

Automobile Body—Care of —A highly fin¬ 
ished body should never be wiped off dry, as it 
is impossible to do this and not scratch the 
polished surface. The best and quickest way is 
to turn a hose on it and then while still wet wipe 
off with a piece of chamois or a soft cloth. 
Waste might be used if of a selected grade, but 
the ordinary cheap kind must never be utilized, 
as it contains small sticks and other hard sub¬ 
stances which will scratch the varnish. 

Automobiles—Types of. Fig. 29 illustrates 
the various types of American Automobiles, both 
gasoline and electric, designated as follows: 

Gasoline. A—Runabout. B—Touring car. 
C—Light car with detachable Tonneau. D— 
Stanhope. E—Roadster. 

Electric. F—Runabout. G—Park trap. H— 
Phaeton. J—Brougham. K—Depot-bus or 
light delivery wagon. 

Axles. So far it has not been found practical 
to combine the tractive, an:l steering functions 
of an Automobile in one set of wheels and axle. 
Therefore it is necessary to use a rigid front axle 
with knuckle jointed spindles, for steering pur¬ 
poses, and utilize the tractive power of the rear 


The Automobile Handbook 


69 


wheels only to propel the car. Some of the 
earlier forms of steering axles had the wheel 
pivots inclined so as to bring the projection of 
the pivot axis in line with the point of contact 
of the wheel with the ground, but as such con¬ 
structions have not proved satisfactory they 
have in most cases been abandoned. 



Fig. 30 


Dead Axle. A dead axle is an axle which 
carries weight only. 

Floating Axle. A special type of live axle 
in which the shaft that turns the wheels is in¬ 
dependent of the axle proper, and may be re¬ 
moved without affecting the axle’s weight car¬ 
rying capacity. 


































70 


•The Automobile Handbook 


Front Axles. Figures 30 and 31 show four 
styles of front axles with steering-pivot ends: 
A shows a solid axle of square section, with 
the steering-pivot jaws and axle proper, of a 
single forging—B represents an axle of tubular 
cross-section with the steering-pivot jaws bored 



out to receive the tubular axle which is firmly 
brazed therein—C shows another style of tubu¬ 
lar axle, in which the steering-pivot jaw ends 
are turned down to fit the inside diameter of 
the tube and are also brazed in position, while 
D illustrates a one-piece axle with vertical hubs 






































The Automobile Handbook 


71 


instead of jaws, which carry L-shaped steering- 
pivots, instead of the usual form of knuckles. 

Live Axle. A live axle is any axle containing 
parts which turn the wheels in addition to carry¬ 
ing weight. 

Rear Axles. A great many medium and 
high-powered cars have a double side-chain 



drive; this necessitates free driving wheels and 
a rigid rear axle with this form of drive. 

Figure 32 illustrates three forms of rigid rear 
axles for the above described form of drive: E 
shows a solid axle of circular section with 
straight spindles for hubs with plain-bearings— 
F, a solid axle of square section with taper 
spindles for plain-bearing hubs, and G an axle 





























72 


The Automobile Handbook 




£&L 







* r 





s s -1 

v» 


t: 

i i 








to 

u 

-J 

X 

< 

q: 

< 

u 

o: 








































































































The Automobile Handbook 


73 


of tabular section with spindles fitted for ball¬ 
bearing hubs. 

Automobiles employing a single chain drive 
from the motor to the rear axle, generally use 
either a live solid rear axle with one driving 
wheel carried upon a loose sleeve attached to 
one of the gears of the differential, or a rigid 
tubular axle with a divided live-shaft, to the 
outer ends of which the driving wheels are 
keyed. Axles of these types are shown in Fig¬ 
ure 33 : If illustrates a solid live rear axle with 
plain-bearings and sprocket on the differential 
gear case. 

Normally both the axle and the sleeve rotate 
in unionism, but on the car departing from a 
straight course or turning a corner, the sleeve 
will move faster or slower than the axle, ac¬ 
cording to the direction of curvature. A rigid 
tubular axle with a divided live driving shaft is 
shown at J; the tubular portions of the axle have 
spiders on their inner ends, which are connected 
around the differential gear and sprocket by 
means of shoulder-studs with nuts, as shown in 
the drawing. The type of axle illustrated at H 
may have either plain or roller-bearings, while 
the type shown at J is usually constructed with 
four sets of ball-bearings, two sets at the outer 
ends of the tubular axle and two sets near the 
center, one on either side of the differential 
case, within the hubs of the spiders. 

In Figure 34, K and L show respectively a 
live solid rear axle and a rigid tubular axle, 


74 


The Automobile Handbook 



ROLLER BEARING AXLES 



































































75 


The Automobile Handbook 

l 

equipped with roller-bearings. The spring lugs 
form part of the roller-bearing boxes of the live 
axle, while they are usually brazed to the tubu¬ 
lar axle near its outer ends. 

A rigid tubular axle with ball-bearing live 
driving shaft is illustrated in Figure 35, the ball- 
cup or race is adjustable by means of a hexa¬ 
gon upon its outer extension in the rear of the 
hub of the wheel and is held securely in position 





■ 

• 




R 



BALL BEARING AXLE 

Fig. 35 

and prevented from turning by means of the 
clamping device shown on the upper portion of 
the bearing. No separate adjustments for the 
inner two sets of ball-bearings are necessary, 
as the teeth of the spur gears of the differential 
which are keyed to the inner ends of the divided 
driving shaft, being free to slide upon them¬ 
selves, allow the shafts M to have a slight longi¬ 
tudinal movement within the axle tube, thus 




















76 The Automobile Handbook 

\ 





























































The Automobile Handbook 


p* rr 
1 ( 

taking up the wear of each pair of ball-bearings 
with a single adjusting mechanism. 

Steering Knuckles. In order to obtain ease 
of operation and secure the shortest turning 
radius with the least movement of the steering 
wheel or lever, the knuckle of the steering pivot 
should be as close to the center of the wheel 
as is possible. It is also cf great importance 
that the steering knuckles should be as heavy 
as is practically consistent with the size and 
weight of the car for which they are intended. 
If this imporant point be neglected, rapid wear 
and probable fracture of the knuckles may be 
looked for. 

A steering knuckle with a spindle and pivot 
of T shape is shown in Figure 36. The spindle 
and pivot N and the steering arms 0 are usually 
a one-piece forging. The steering arms (3 are 
connected by means of a suitable distance rod 
and the steering lever P is attached to one of 
the pivots N by turning a shoulder upon it and 
pinning and brazing the steering lever and pivot 
hub together. 

Figure 37 shows a steering knuckle with 
spindle and pivot of L shape. The steering arm 
R goes on the lower end of one pivot Q only, 
the other pivot having the combined steering 
arm and ever S on its lower end. The steering 
arms being detachable, the device may be oper¬ 
ated from the right or left hand side by simply 
exchanging the levers R and 8. The steering 
lever S has a ball upon its outer end to fit in the 


78 


The Automobile Handbook 



STEERING KNUCKLE 

Fig. 


«> i 






















































2 lie Automobile Handbook 


79 

socket on the connecting rod of the steering 
mechanism. 

Backfiring, Causes of. This is a term applied 
to an explosion or impulse which forces the 
flywheel of a motor suddenly backwards, that 
is, in the opposite direction to its proper rota¬ 
tion. The term is sometimes used in connection 
with explosions which occur in the muffler from 
the ignition of an accumulation of unburned 
gases. 

When a back kick occurs and the crank-shaft 
rotates in the reverse direction, that rotation 
must first be stopped and a rotation started in 
the correct direction. To stop the back kick or 
reverse rotation requires power, and to again 
start the correct rotation calls for power. The 
forces that stop the back kick are, the arm of 
the person cranking the weight of the rotating 
flywheel, and forcing one of the other pistons 
to compress the mixture. The force that starts 
the flywheel in the correct direction is the ex- 
illustrated in Fig. 38, in which the piston in 
No. 1 cylinder has not reached the top dead 
center on the compression stroke when the 
spark occurs and the reverse movement of the 
crankshaft starts. In tracing out what happens 
the valve locations must be considered. Both 
valves—intake and exhaust—in No. 1 cylinder 
are closed on the compression stroke and they 
will remain closed on the back kick stroke. 
Had the motor been running, No. 2 cylinder 
would have been going down on the explosion 


80 


The Automobile Handbook 



Fisr. 38 












































































































The Automobile Handbook 


81 


stroke of the piston, but as there was no previ¬ 
ous explosion, the motor having been idle, the 
cylinder would be tilled with mixture, with 
both valves closed, as they always are on the 
explosion stroke. The piston in this cylinder 
was normal^ going down; but, as soon as the 
back-fire occurred, the piston would start up 
and the valves remaining closed, the mixture 
would be compressed. This pressure would help 
to stop the back kick, and as soon as the power 
of back-kick was over the compression would 
start the piston down on the proper explosion 
stroke, which would prove of sufficient power 
to carry the motor past the firing point in the 
other cylinders. Cylinders 3 and 4 would not 
be factors .at all, in that the piston in No. 3 
would, when the back-kick occurred, be near 
the bottom or end of the suction stroke with the 
intake valve open, and when the reverse action 
of the piston set in it would start rising, simply 
driving the mixture out through the open intake 
valve and through the carbureter. Cylinder No. 
4 was near the completion of the exhaust stroke 
when the back-fire started, and the exhaust 
valve was open. During the reverse motion 
caused by the back fire, the piston would start 
descending, the exhaust valve remaining open, 
exhaust gases would be drawn into the cylinder 
from the exhaust pipe. 

Other causes of back firing are, 

(1) A weak mixture. Bearing in mind that 
the mixture is the fuel of the engine, and that 



82 


The Auto mob iit Handbook 


as in a stove, the character of the fuel influences 
its manner of burning', it will be evident that 
like poor wood, slaty coal, or other imperfect 
fuel, a weak mixture is a slow burner. This is 
point number one. Proportionate to the speed 
at which it is running, the motor has a certain 
sharply defined period of time in which it must 
complete each part of its cycle, if it is to operate 
satisfactorily. Should the parts of the cycle 
lap, or run over into one another, there is bound 
to be a hitch of some kind. The use of a very 
weak mixture causes just such a hitch by rea¬ 
son of the fact that it continues burning for 
some time after the completion of the part of 
the cycle during which it is supposed to func¬ 
tion, i. e., the power stroke. In fact, it is still 
burning when the inlet valve opens to take in 
a fresh charge, and as its burning in the cylin¬ 
der maintains considerable pressure therein, the 
latter, on the lift of the inlet valve, escapes 
through it and the carbureter with a pop. 
exactly similar to that of an unmuffled exhaust 
except that it is weaker. The remedy is more 
gas or less air, or sometimes both, and to find 
out just how much of each is required, start 
the motor and very gradually cut down its 
gasoline supply at the needle valve of the car¬ 
bureter until the motor begins to miss. Then as 
slowly increase the supply until the motor will 
run steadily and without missing on the mini¬ 
mum opening of the needle valve. Lock the 
latter in place. Then speed the motor up by 


The Automobile Handbook 83 

opening’ the throttle and adjust the spring of 
tlie auxiliary intake on the carbureter until the 
motor is receiving sufficient air to enable it to 
run and develop plenty of power at all speeds. 

(2) An overheated combustion chamber, 
due to a poor circulation of the cooling water— 
causing self-ignition of the charge before the 
proper time. 



Fig. 39 
Cone Bearing 


(3) Advancing the ignition point too far 
ahead when the motor is running slowly under 
a heavy load—flywheel has not sufficient mo¬ 
mentum to force the piston over the dead cen¬ 
ter, against the pressure of the already ignited 
and expanding gases. 

(4) The presence of a deposit of carbon 
(soot) or a small projecting surface in the com¬ 
bustion chamber which may become incandes¬ 
cent and cause premature ignition. 






























84 


The Automobile Handbook 


Ball Bearings. Ball bearings may be broadly 
divided into three classes—thrust, cone and an¬ 
nular. Thrust bearings are those intended to 
sustain end thrust, and in them care must be 
exercised to see that the points of contact of 
the balls are exactly opposite, and that the 
grooves in which the balls run are formed to a 
sectional radius a little larger than that of the 
balls, thereby securing safe and easy move¬ 
ment of the balls. These grooves must be de¬ 
signed not only to give smooth rolling contact, 
but so that a measurable area of the ball's sur¬ 
face contacts with the race. It is also possible 
for a thrust bearing to act at the same time as 
a radial bearing, in which case, however, the 
four-point system must be used. In thrust bear¬ 
ings the balls are constantly under pressure and 
table 7 gives suitable loads for equal shaft diam¬ 
eters and revolutions for different sizes and 
numbers of balls: 


TABLE 7. 


Shaft 
Diameter, 
in inches. 

Allowable 

Load 

lbs. 

R.P.M. 

Number 

of 

Balls 

Ball 

Diameter 
in Inches 

2.55 

550 

500 

90 

% 

2.55 

1.000 

500 

15 

% 

2.55 

1.200 

500 

14 

11/16 

2.55 

1,800 

500 

13 

% 

2.55 

1,600 

500 

12 

% 

2.55 

1.S00 

500 

10 

1 


The adjustable cone bearing, Fig. 39, has been 
used in millions of bicycles with excellent re¬ 
sults, but under large loads has been found in¬ 
adequate. A ball can roll freely only with op¬ 
posite points in contact, and every third or 














The Automobile Handbook 


85 


fourth point of contact involves more or less 
spinning, or sliding movement of the ball, which 
shortens its life, and the bearing must operate 
to the detriment of the contact surfaces. 

The third and great type of ball bearing is 
the so-called annular one intended for radial 
loads. It consists of three elements—two races 
and the balls. The new annular bearings re- 
quire no adjustment or fitting, and the rolling 
action of the balls takes place without interfer¬ 
ence of friction. A wonderful advantage of 
this bearing is that as high as 96 per cent of the 
space between the races can be filled with balls, 
the balls being introduced through filling lots 
whose size is a little less than the diameter of 
the balls to be introduced, so that the balls are 
forced between the two races under pressure 
and by virtue of the elasticity of the material. 
In the annular bearing but 30 per cent of the 
balls are under load at one time, and it is pos¬ 
sible for equal axle sizes and speeds to use dif¬ 
ferent dimensions and loading according to 
the size of the balls. Table 8 gives suitable 
loads for equal shaft diameter, and revolutions 
for various sizes, and numbers of balls. 


TABLE 8. 


Shaft ( 

Diam. 

inches 

Allowable 
load on R. P. M. 

Bearing', lbs. 

No. of 

Balls 

Diam. of 
Balls, 
Inches 

3.14 

1,000 

500 

20 

y 2 

3.14 

1.300 

500 

21 

rs 

3.14 

2,500 

500 

12 

1 

3.14 

3,000 

500 

14 

ItV 

3.14 

4.500 

1 500 

11 

1* 














86 


The Automobile Handbook 


Annular ball bearings are also made with two 
rows of balls, and in the majority of them each 
ball is in a separate cage. Experiments have 
proven that, where the balls contact with one 
another, after a few years the friction results in 
grooves being worn in them. In Fig. 40 is shown 
the form of separator used in the F. & S. bear¬ 
ings. If in the application of this bearing it is 



F & S Bearing Separator 


necessary to sustain heavy axle loads, it is ab¬ 
solutely necessary to add an independent thrust 
bearing, or to employ a combination bearing 
which takes the place of bolt thrust and radial 
loads. 

Ball Bearings—Two in One. Figs. 41. 42, 
and 43 illustrate a ball bearing manufactured 
at Bristol, Conn., which, owing to its dual ability 

























The Automobile Handbook 


87 


a* expressed by its name (“two in one”) is 
especially adapted to automobile service. Its 
makers claim that it is able to withstand radial 
or thrust loads, or any combination of the two, 
with the use of but a single bearing with its 
attendant simplicity of mounting. In order to 
bring about this result, two rows of balls are 
employed in staggered relation to one another, 
and the ball races are so arranged that the line 



Fig. 41 

Assembled Bearing Complete 


of pressure is either at an angle of 45 degrees 
or 60 degrees with the horizontal, when the axis 
of rotation of the bearing is in a horizontal 
plane. 

Figure 41 shows the permanent assembly of 
the bearing, sufficient metal being provided in 
the shell to permit of drawing the latter tightly 
over the cups. 


88 


The Automobile Handbook 


Figure 42 shows the various parts of this 
bearing, and Fig. 43 is a semi-sectional view 
showing the order of their assembly, from the 
shaft outward, as follows: the cone, the separa- 
tor, the two cups and the shell. It will be no¬ 
ticed that the line of pressure of the cone, cups, 



Fig. 42 


and balls is at an angle of 45 degrees with the 
horizontal, and this feature applies equally to 
both rows of balls, thus adapting the bearing 
to withstand a load from any angle. Two semi¬ 
circular races are turned in the cone to receive 
the balls, while the sheet metal separator is so 
stamped that the ball retaining notches are 



















The automobile Handbook 


89 


staggered with reference to each other. These 
openings are made slightly larger than the ball 
diameter, so that the contact between the ball 
and separator is said to be a point contact at 
one end of the axis of rotation, while the weight 
by separator is carried on the balls at the top 
of the bearing. By maintaining the relative 
positions of the balls at all times, cross friction 



Fig. 43 

Sectional View of Bearing 


it is claimed is entirely eliminated, while the 
friction introduced by the use of the separator 
is practically negligible. 

Ball Bearings—Lubrication of. Ball bear¬ 
ings must be so housed in as to retain lubricant 
and exclude dust, grit, etc. An impression that 
ball bearings will operate without lubricant is 
quite general. It is barely possible that abso¬ 
lutely true spheres might roll on absolutely 



Hyatt Self-Oiling Self-Contained Roller Bearing 





The Automobile Handbook 


91 


true surfaces if both were made of materials 
that were absolutely inelastic, and therefore 
would remain true under load. But since such 
absolute perfection of the shape is not to be had, 
some means must be taken to provide and re¬ 
tain lubricant. 

Rust and acid must be kept out of ball bear¬ 
ings. Experience and most carefully conducted 
tests have proven that long life under load can 
be realized from ball bearings only when the 
surfaces are not only true, but are also highly 
polished and smooth. Roughness will be broken 
down and leave still greater roughness. Rust 
and acid will destroy originally true and smooth 
surfaces. Since not a few lubricants contain 
free acids, care in their choice must be exercised. 
Plentiful lubrication and a properly closed 
mounting are safeguards against rust. 

Ball and Socket Joints. To produce a flexible 
joint capable of operation within certain limi¬ 
tations in any direction, the ball and socket 
form of joint is generally used on the ends of 
the rod which connects the arm of the steering 
mechanism with the steering lever attached to 
the hub of one of the steering pivots of the 
front axle. 

Batteries—Dry. A dry battery of the usual 
type consists of a zinc cell which forms the 
negative element of the battery. The electro¬ 
lyte is generally a jelly-like compound contain¬ 
ing sal-ammoniac, chloride of zinc, etc. The 
carbon or positive element is enclosed in a sack 



92 


The Automobile Handbook 


or bag containing dioxide of manganese and 
crushed coke, which are the depolarizing agents 
of the battery. 

Dry batteries which have become exhausted 
may in most cases be recuperated in the follow¬ 
ing manner: First disconnect the cells from 
each other and remove their pasteboard covers, 
then drill a hole in the sealing compound on 
top of the cell, about one-quarter of an inch 
in diameter and at least 2 inches in depth so as 
to insure getting below the sealing compound. 
Take 1 ounce of bisulphate of mercury and put 
in a porcelain or earthenware vessel (on no ac¬ 
count use a metal vessel) and pour over it one- 
half pint of boiling water—when cold, draw off 
the clear solution, being careful not to disturb 
the yellow precipitate left at the bottom of the 
vessel, which is useless and should be thrown 
away at once, as it is a rank poison. Dissolve 4 
ounces of sal-ammoniac in 1 pint of hot water 
and when cold mix with the first solution and 
the recuperative agent is then ready for use. 
Take a small glass funnel, or a tin one that is 
thoroughly painted or enameled, and introduce 
about a tablespoonful of the liquid into each cell 
through the hole already drilled for this pur¬ 
pose. The liquid must be introduced into the 
cells very slowly, as it will take a long time 
to absorb, and the cells should be allowed to 
stand at least 12 hours after filling before being 
ready for use. 

Primary Batteries. When there is no in- 


The Automobile Handbook 


93 


candescent light circuit at hand or the electric 
current is of the alternating type, primary bat¬ 
teries of some form or other are very useful to 
charge small storage batteries which are used 
for ignition purposes. 

The voltage of a set of primary batteries to be 
used for charging a small storage battery, 
should exceed the voltage of the storage bat¬ 
tery by at least 30 per cent. 

Primary batteries of the open-circuit type, 
such as sal-ammoniac cells, are useless for charg¬ 
ing purposes, only batteries of the closed-cir¬ 
cuit, or constant current type are suitable. 

A very simple and inexpensive form of closed 
circuit battery for charging purposes is the 
single liquid type, which uses zinc and carbon 
electrodes in a 20 per cent solution of sulphuric 
acid and water, with nitrate of soda as the de¬ 
polarizing agent. 

For a 4 volt storage battery four such cells 
are required, while for a 6 volt storage battery 
six cells will be necessary for a proper charge. 

This form of primary battery has a voltage 
of 1 % volts per cell. 

The articles necessary for a complete charg¬ 
ing outfit are as follows: One small pocket am¬ 
meter reading up to 5 amperes, one two-point 
switch, one resistance coil or rheostat (home 
made), one set of closed-circuit type of pri¬ 
mary batteries, and about 25 feet of No. 16 B. & 
S. Gauge, Okonite or Kerite stranded copper 
wire for the connections. 


94 


The Automobile Handbook 





tj 

f*. 


WIRING DIAGRAM 


























































































The Auto mobile Handbook 


95 


The method of connecting the primary bat¬ 
teries, resistance coil (rheostat), ammeter and 
switch is plainly shown in Fig. 44. The positive 
pole of the primary battery should always be 
connected with the positive pole of the storage 
battery, the carbon element is always the posi¬ 
tive electrode in both dry, and primary forms 
of batteries. If the polarity of the terminals 
of the storage battery are not indicated on the 
case by the + and — signs, which represent 
positive and negative respectively, their polarity 
may be readily ascertained by means of a piece 
of moistened litmus paper (paper soaked in a 
solution of iodide of starch). Place the piece 
of moistened litmus paper on a board or other 
non-conducting material and bring the wires 
from the storage battery terminals into contact 
with opposite ends of the paper for a few sec¬ 
onds only—one end of the paper will turn red, 
this will be next to the wire connected with the 
negative pole of the storage battery. 

The resistance coil or rheostat may be made 
very simply as follows: Take a piece of hard¬ 
wood 3 inches square and 15 inches long and 
turn down about 13% inches of its length to a 
diameter of 2% inches in the manner shown. 
Upon this turned part cut with a round-nose 
tool a groove or thread one-sixteenth of an inch 
deep, with 8 threads to the inch. In this groove 
wind about 50 feet of No. 18 B. W. Gauge bare 
soft iron wire and connect with a bar and slid¬ 
ing contact as shown in the drawing. 


96 


The Automobile Handbook 


To charge the storage battery, move the slid¬ 
ing-contact to the right until all the resistance 
is in use, then move the switch-finger to the 
point on the left and adjust the sliding-contact 
by moving it to the left until the ammeter shows 
3 amperes. Moving the switch-finger to the 
right will put the battery in the circuit for 
charging, and the sliding-contact should be 
again adjusted until the ammeter shows 3 am¬ 
peres. The sliding-contact should be adjusted 
from time to time to keep the charging current 
at 3 amperes. 

If the storage battery be of 12 ampere-hour 
capacity it will take 4 hours to properly charge 
it, if of 18 ampere-hour capacity, 6 hours. The 
ampere-hour capacity of the battery divided by 
the amperes of the charging current gives the 
number of hours* required to fully charge the 
battery when exhausted. 

After the storage battery is fully charged the 
electrodes should be lifted out of the solution 
as shown in the drawing, by means of the cover 
to which they are shown attached, until the bat¬ 
tery is again required for use. 

Selecting a Battery for Ignition. Practi¬ 
cally every gas engine works most satisfactorily 
with a 6-volt battery. However, in some in¬ 
stances a lower or higher voltage is frequently 
required, owing to the variation in the com¬ 
pression, and the style 6f coil and ignition equip¬ 
ment used. 

If dry cells are used, figure one dry cell for 


The Automobile Handbook 


97 


each volt of storage battery. For instance: 3 
to 4 dry cells will require 4-volt storage; 5 to 6 
dry cells will require 6-volt storage; 7 to 8 dry 
cells will require 8-volt storage. 

Battery Connections. There are a consider¬ 
able number of methods which may be used for 
connecting the ignition devices in the cylinder 
to the source of current, each of which involves 
different forms of apparatus and different 
methods of connections, especially in the jump- 



spark systems. The make-and-break systems, 
owing to their comparative simplicity, do not 
differ very much in the method of connection. 

Two methods are usually employed, viz.: 
series, and multiple, or parallel. To connect 
dry batteries in series, the terminals are joined 
alternately, that is, the zinc of the first is con¬ 
nected to the carbon of the second, the zinc of 
the second to the carbon of the third, etc. 

When so joined, the positive element is left 
free at one end, and forms the positive terminal 



















98 


The Automobile Handbook 


of the group, which is then considered as a unit. 
The other free end (the negative) forms the 
negative terminal of the unit, see Fig. 45, which 
shows four cells connected in series. 

Figure 46 shows four cells connected in paral¬ 
lel which means that all of the positive termi¬ 
nals are connected to one common wire, and all 
negatives are connected to another wire. 

This mode of wiring up the cells gives a 
smaller output for the group. Thus if the in¬ 
dividual batteries have an internal resistance 



Fig. 46 

Parallel Connections are Not as Frequently Used 

which is low in comparison with the external 
resistance, the total output will be but slightly 
more than that of a single cell. If, on the other 
hand, the internal resistance is high relative to 
the external, the current will be roughly pro¬ 
portional to the number of cells. 

Where the cells are divided into sets or groups 
of a small number (four is usual), and more than 
one of these sets are used at a time, there are 
again two methods of joining them; These two 
are the same as before, viz., series and multiple. 


















The Automobile Handbook 


99 


The former is very seldom used, if ever, but mo 
other is rather common. When two or more 
sets of batteries, themselves connected in series 
are, as sets, joined in multiple the whole is 
spoken of as connected in series-multiple. 



Batteries—Storage. A storage battery as 
used in ignition service, is usually of the lead, 
lead type, in which the electrolyte is sulphuric 
acid and water of a density about 1.2— specific 
gravity. The plates are of two classes—posi¬ 
tives and negatives—there being one more nega¬ 
tive than positive in each nesting in a ceil. 
The elements of a cell of storage battery are 

















































100 


The Automobile Handbook 


given m Fig. 48, and consist of the following: 
Positive plates A, of which there is one fewer 
than of negatives; negative plates B, of which 
there is always one more than positives; sepa- 



Fig. 48 

Elements of Assembled Battery 


rators C, which may be of wood, rubber, oi 
other suitable material, and if of wood must be 
treated; positive strap D, the function of which 
is to connect all the positive plates, across the 








The Automobile Handbook 


101 


top, into electrical relation; negative strap E, 
the function of which is to connect all the nega¬ 
tive plates, at the top, in electrical relation; bat¬ 
tery jar F, made of rubber composition, light, 
strong and acid proof; cover for the jar G, with 
holes for the terminals of the elements, and a 
vent; assembled cell of battery H, showing the 
elements in place, separated, with cover on; 
ready for connections; and a battery box I, of 
oak, usually contrived to hold three cells of 
battery, sometimes two. 

The positive and negative plates, called ele¬ 
ments, consist essentially of a grid in each case, 
made of lead-alloy, in which antimony is used 
to engender stiffness. The grids are in divers 
forms, depending upon the view's of several 
makers, the idea being to afford space for the 
active material, and to lock the same in, so that 
it will not drift out, as it is prone to do, under 
the action of the charging, and discharging cur¬ 
rent. Surface is the great requisite, and it is 
the aim to afford the maximum area of the fin¬ 
ished plates, per pound of active material used; 
limiting the weight of the supporting grid, in 
so far as it is possible to do so. 

The voltage of a battery of this type is usu¬ 
ally 2.2 volts when the circuit is closed, but it 
drops to 2 volts within the first hour of using, 
which pressure it usually maintains during the 
next 5 hours, after which the voltage declines 
at a rapid rate. 

Adding Water to Cells. In service water 


102 


The Automobile Handbook 


will have to be added to the cells to compensate 
for evaporation, and for the loss that takes place 
during charge, brought about by the entraining 
of water with the bubbles of gas that shoot off 
and out of the jars, if they are open, that is to 
say, if the covers are removed before and left 
off during charging, which is not usually the 
case. The result in any event is in favor of in¬ 
creasing strength of the electrolyte, and water 
will have to be added from time to time in order 
that the plates may not be exposed to the atmos¬ 
phere above the line of active material; which 
is a point that must be cared for if the battery 
is to last for a long time. The water so added 
should be pure—distilled—and the right quan¬ 
tity to add, will be determined bv means of a 
hydrometer placed in each cell between the sepa¬ 
rators if there is sufficient room, or the electro¬ 
lyte may be withdrawn through the utility of a 
gun made of hard rubber with a long slender 
neck. The test should be made when the bat¬ 
tery is charged and every cell should be exam¬ 
ined rather than to test one cell and conclude 
that all are in an average condition. 

Storage Batteries—Care of. Among the 
troubles that ultimately attend batteries in serv¬ 
ice the following are the most conspicuous: 

Hardening of negative elements; local action ; 
buckling of plates; shedding of active material; 
sulphation; reversal of negative elements; dis¬ 
integration of grids; protruding active mate¬ 
rial ; deformation of separators; broken jars; in- 


The Automobile Handbook 


103 


cipient short circuits; defective electrical con¬ 
tact ; loss of capacity; loss of voltage; corrosion 
of plates, and needle formations. 

Hardening of the negative elements will fol¬ 
low if they are exposed to air, as when the elec¬ 
trolyte is allowed to fall below the level of the 
plates, from any process that will produce over- 
oxidization if the temperature is allow r ed to in¬ 
crease much above 90 degrees Fahrenheit. 
When the negative elements are hard, to reduce 
them back to the normal condition, assuming 
the process is not too far gone: Remove the 
elements from the jar, place the negatives in a 
cell, with dummy positives, and charge until 
the negatives are corrected, taking care not to 
charge at a too high rate. High temperature 
and excess boiling should be avoided. If the 
negatives are charged in their own cell with 
the regular positives the positives will be dam¬ 
aged by the excess charging that will be neces¬ 
sary to reduce the negatives. When the nega¬ 
tives are sufficiently charged to correct the evil 
they may be returned to their own cell, and 
when connected up with the positives the cell 
will be ready to go into service again, if in the 
meantime the positives are given such attention 
as their condition would seem to indicate. Local 
action, following impurities in the electrolyte, 
will only be prevented as much as it is possible 
to do so when the electrolyte is removed and 
pure electrolyte substituted in its stead. This 
should be done when the cells are fully charged. 


104 


The Automobile Handbook 


The electrolyte will hold most of the impurities 
when the battery is in the fully charged state. 

Buckling of plates, when batteries are defec¬ 
tive in design, rather than in cells of normal 
characteristics, is a trouble that will follow in 
any cell if the discharge is allowed to extend 
below 1.8 volt as indicated by the cadmium test, 
rather than by the usual potential difference 
reading across the two sets of elements in the 
cell. If the rate of discharge is excessive, a 
condition that is not likelv in ignition work, 
buckling will follow also. Short-circuiting the 
elements to see if the battery is alive will tend 
to buckle the plates, due to the heavy discharge, 
and the uneven rate of discharge over the sur¬ 
faces of the elements. In defective construction, 
if the active material is not of the same porosity, 
thickness, and in the same condition all over the 
surfaces of the plates, buckling will follow. 

Shedding of the active material, ‘to a slight 
extent, is a normal condition of batteries; and 
to prevent trouble due to incipient short cir¬ 
cuits, such shedding is cared for by having a 
space in the bottom of cells to hold such 
shedded material. When elements are of in¬ 
ferior design and improperly constructed the 
active material will shed at a rapid rate, and 
the user of the battery can do nothing more than 
demand a new battery to replace the defective 
one. If charging is done at a too rapid rate 
the active material will be loosened by the rap¬ 
idly escaping gas, and even on discharge, if the 


The Automobile Handbook 


105 


rate is high, the shedding of active material is 
likely to follow. 

Sulphation, which is a normal expectation 
during discharge of a battery, introduces serious 
complications under certain conditions as when 
the active material is not in intimate contact 
with the grids thus allowing the electrolyte to 
get between the grids and the active material, 
with the result that sulphate, which is a high 
resistance material, isolates the grids and re¬ 
duces the efficiency of the cell in two ways; 
first, by increasing the ohmic losses, and, second, 
by lowering the chemical activity. Excess sul¬ 
phate is prone to form when the electrolyte is 
out of balance, and one of the best ways to 
abort this action is to keep the electrolyte with¬ 
in the prescribed limits of strength. If sulphate 
is allowed to form until white crystals show over 
the surfaces of the plates, it is highly improb¬ 
able that the cells will ever be of sufficient serv¬ 
ice to warrant continuing them in service. The 
only way to afford relief lies in reducing the 
growth of sulphate by continuous charging the 
sick elements in a cell with dummies until the 
sulphate is reduced. A slow rate for a long 
time may bring about a reform. 

Negative elements to be reversed must be 
below capacity, or the cells must be discharged 
to zero and then reversed. In charging it is 
always necessary to make sure that the eonnec- 
tions are made in such a way that current will 
flow into the battery, rather than out of it. Volt- 


106 


The Automobile Handbook 


meters in which permanent magnets are used 
will serve as polarity indicators, and with them 
it is possible to proceed with safety. If a bat¬ 
tery is connected up in reverse when it is put on 
charge, instead of being charged it will be dis¬ 
charged, and then charge in reverse. While it 
is discharging it will deliver current to the line. 

Disintegration of grids will follow if the im¬ 
purities are allowed to enter the electrolyte, as 
iron, etc. Continued charging will also have 
the effect of reducing the grids to form salts 
of lead. 

Protruding active material, due to expansion 
and displacement of the same, indicates a lack 
of binding relation between the grids and the 
active materials. There is no remedy. Defor¬ 
mation of separators, when they are made of 
rubber compound, follows when the cells are 
allowed to heat beyond a certain point. This 
trouble will be aborted if the cells are charged 
at a normal rate, and if the temperature is not 
allowed to increase beyond about 90 degrees 
Fahrenheit. When wood separators are used 
they will slowly rot and in time it will be neces¬ 
sary to replace them. 

Broken jars will allow the electrolyte to leak 
out, and frequently the fracture is but a minute 
crack, so that it is well to be on the lookout 
for just this kind of trouble. If the jars are 
properly nested and motion between them is 
prevented they will as a rule serve without 
breaking. 


The Automobile Handbook 


107 


Incipient short circuits are likely to go an- 
. ccl« ^ ai e generally due to detached 
particles of active material that lodge between 
the plates, especially in vehicle and ignition 
types, owing to the short distance separating 
the plates, and the use of separators, such as 
perforated rubber in the absence of wood, which 
have the virtue of being porous but too close to 
allow the active material to bridge across the 
space between the plates. 

Defective electrical contact is due to corrod¬ 
ing of joints that are not made by burning. 

Loss of capacity may be traced to such causes 
as: If the electrolyte is out of balance or below 
the level of the top of the plate; loss of active 
material from the grids; sulphate formed on 
the surfaces of the grids, Isolating the active 
material; lack of porosity of the active material; 
impurities and sulphate clogging up the pores 
of the active material; low temperature; high 
temperature; persistent sulphation, and inter¬ 
cell leakage due to electrolyte spilled over the 
surfaces, especially if jars are in actual contact 
with each other. 

Loss of voltage, as distinguished from loss of 
capacity, follows in a battery when one or more 
of the cells are dead or below voltage. If one 
or more of the cells are reversed they will set up 
a counter-electro-motive force, and the over-all 
reading of the battery will be reduced accord¬ 
ingly. The remedy is obvious. All the cells 


108 


The Automobile Handbok 


should read the same way, and all should have 
the same difference of potential, respectively. 

In view of the sulphated condition that at¬ 
tends all batteries that are discharged at a low 
rate for a long time, as is the case in ignition 
work, it is necessary to charge at a low rate for 
a long time in order to reduce the sulphate, 
which is in persistent form and very difficult 
to reduce. It will not be enough to correct the 
strength of the electrolyte once during the 
charging process for the reason that it will be 
difficult, if not impossible, to ascertain the con¬ 
dition of the same with any degree of accuracy, 
and the necessity for noting strength two or 
three times in the act of charging is apparent. 
When the battery is fully charged, which may 
take even sixty hours of continuous charging 
at a low rate, the electrolyte in every cell should 
stand at full strength, considering a state of 
full charge, and the color as well as other indi¬ 
cations of a full charge should be fully noted. 
Boiling at a slow rate should be tolerated for 
several hours, but the temperature should be 
held at about 90 degrees Fahrenheit during the 
entire time. If a battery is charged at frequent 
intervals it will last longer in service, give less 
trouble in charging and will be more reliable in 
service. It is well to begin charging directly a 
battery is taken out of service as any delay 
after that time will result in a marked deteriora¬ 
tion of the cells. 

When a car is put out of commission, even 


The Automobile Handbook 


109 


for a few weeks, the battery should be given a 
light discharge, and a subsequent charge as 
often as once a week, until it is again brought 
back into use. 

Storage Batteries — Charging. Positive 
plates in the charged state are of a velvety 
brown or chocolate color; negative plates have 
the color of sponge lead, which is very nearly 
light gray. When a battery is approaching a 
condition of full charge the color tones up quite 
noticeably, and it is possible to mistake a con¬ 
dition of full charge, if color alone is taken as 
the evidence; the exterior will have the appear¬ 
ance of full charge, since the active material, 
on the exterior surface, will reach its charged 
form first; if the thickness of active material on 
the grids is very thick, as it is likely to be in 
low discharge rate work, charging by color, 
as evidence of a state of full charge, will be to 
limited advantage. Details regarding correct 
methods of charging storage batteries are given 
under the head of Primary Batteries. 

Storage Batteries—Testing. Tests for im¬ 
purities in the electrolyte may be made as fol¬ 
lows. For iron ; 

Neutralize a quantity of the electrolyte to he 
investigated, after diluting the same, by the 
addition of an equal amount of pure distilled 
water, using strong ammonia water for the pur¬ 
pose. To the solution, so neutralized, add one- 
thirtieth of the amount of the same of hydro¬ 
gen peroxide* thus reducing any iron present 


110 


The Automobile Handbook 


to the ferric state. If a sample of this solution 
is rendered alkaline by the addition of a suffi¬ 
cient quantity of ammonia water, then, if iron 
is present, enough to amount to anything of 
great moment, from the battery point of view, 
a brownish red precipitate will form. A test 
for chlorine is as follows: 

Make a solution of nitrate of silver in the 
proportion of 20 grams of the same, in 1,000 
cubic centimeters of pure distilled water, and 
add a few drops of this solution to a small quan¬ 
tity of the electrolyte to be investigated; if 
chlorine is present the solution will turn white, 
owing to the formation of chloride of silver, 
which will precipitate out. 

A test for nitrates is as follows: In a test tube, 
holding 25 cubic centimeters of electrolyte to be 
tested, add 10 grams of ferrous sulphate; to 
this carefully add 10 cubic centimeters of chem- 
ically-pure sulphuric acid by pouring the same 
slowly down the side of the tube; in the pres¬ 
ence of nitric acid, a brown solution will form 
between the electrolyte to be tested, and the 
concentrated solution of sulphuric acid. 

The presence of copper may be detected from 
the fact that when ammonia solution is added 
to electrolyte, a bluish-white precipitate will 
form. In testing for mercury, lime water, if it 
is added to electrolyte in which mercury is pres¬ 
ent will evolve a black precipitate. Testing for 
acetic acid is as follows: To a small quantity 
of the electrolyte to be tested, add enough am- 


The Automobile Handbook 111 

monia water to render the same neutral; ferric 
chloride added to this solution will cause the 
same to turn red in the presence of acetic acid 
and the solution will then bleach, provided 
hydrochloric acid is added, thus affording con¬ 
clusive proof of the presence of the undesired 
acetic acid. 

Bearing's. The bearings of an automobile, 
although classed among the smaller parts of 
the machine, are nevertheless very important 
factors, and if not properly constructed, and 
cared for will cause much unnecessary friction. 
The essentials of a good bearing metal are; (a) 
that it shall possess high anti-frictional proper¬ 
ties, and be able to withstand heavy pressures 
at high speeds, without heating; (b) it should 
be of sufficient hardness to prevent it from being 
squeezed out of place under heavy loads, or be¬ 
ing cracked or broken under severe shocks, or 
blows; (c) it should be easily renewable when 
worn out. Ball bearings having been already 
described it is unnecessary to again allude to 
them, except to say that while they cause less 
rolling friction than do plain bearings, still they 
involve considerable loss of power, due to the 
fact that they roll in opposite directions, and 
consequently rub against each other, with the 
result that the balls soon wear out. 

Hard and Soft Bearings. There are two 
general classes of solid bearings, those which 
contain a large per cent of copper and a small 
amount of the softer metals; which are known 


112 


The Automobile Handbook 


as hard metals, as brass or bronze. Those which 
contain a large proportion of tin or lead and a 
small per cent of copper are known as soft 
metals—as babbitt-metal, anti-friction metal and 
Ivhite metal. 

In some instances and under certain condi¬ 
tions it has been found that a good close-grained 
cast iron makes an excellent bearing metal. 
Being of a granular nature, it has the property 
of retaining the lubricant in place, even when 
highly polished and under great pressure, with 



Types of Plain Bearings 


a low co-efficient of friction, but is too brittle 
to withstand severe shocks. 

Plain Bearings. Plain solid bearings are 
used on many parts of an automobile, particu¬ 
larly in the engine and transmission bearings, 
although ball and roller bearings are taking 
their place in many constructions. The major¬ 
ity of the cars use brass, bronze or babbitt-metal 
on the main and crankshaft bearings, while ball 
and roller bearings are used on the transmission 
and wheel bearings. A typical plain bearing is 
shown in Fig. 49, in which A is the journal made 
of steel, while the bearing members shown at 





















The Automobile Handbook 


113 


B. B. are made of either brass, bronze, or babbitt 
metal. Figures 50 and 51 show different types 
of connecting rod bearings. For plain-bear¬ 
ings, the shafts of which are continuously run¬ 
ning at a high rate of speed, such as motors 
and speed-change gears, the working pressure 



Fig. 51 

Solid Connecting Rod Bearing 


per square inch should not exceed 400 pounds. 
As the arc of contact or actual bearing surface 
of a journal bearing is assumed as one-third of 
the circumference of the journal itself, the pres¬ 
sure per square inch upon a bearing is therefore 
equal to the total load upon the bearing, divided 














114 


The Automobile Handbook 


by the product of the diameter of the journal 
times the length of the bearing. 

Let D be the diameter of the journal or shaft 
at its bearing, and L the length of the bearing, 
if W be the total load or pressure upon the bear ¬ 
ing and P the pressure in pounds per square 
inch of bearing surface, then 

W 

Pr=- 

DXL 

If the total load or pressure on the bearing 
be known and the diameter of the shaft given, 
then the proper length of the bearing will be 

W 

L =- 

D X P 

If the length of the bearing be known and 
other conditions as before given, then the proper 
diameter of the journal will be 

W 

D =- 

PXL 

When fitting a new bushing to a wheel the 
spindle should first be removed from the axle, 
placed in a lathe, and tested to see .if it is true, 
and if not true a slight cut taken off to true it 
up. Next fit the bushing in the wheel, then the 
wheel on the spindle. If the spindle is slightly 
bent or twisted the wheel may run free when 
the car is jacked up, but hard under a load. If 
a bushing is first fitted to a spindle and then 





The Automobile Handbook 


115 


driven into the wheel, it will probably be too 
tight when placed on the spindle. 

The length of a plain-bearing^ should not be 
less than the following proportions: 


C 



One and one-third diameters for crank-shaft 
wrist-pin bearings. 

Two diameters for crank-shaft bearings. 

Two and one-half diameters for speed-change 
gears. 

Three diameters for live rear axles. 




























116 


The Automobile Handbook 


Four diameters for wheel hub bearings. 

Bevel Gear Differential. Figure 52 shows a 
bevel gear differential in which A and B are the 
two halves of the rear axle, which is divided at 
its center. One of the driving wheels is carried 
on A, and the other one on B, while the inner 
ends of the two half axles are each fitted with 
bevel gear wheels C and D. Meshing with 
these two bevel gears are two, three or four 
bevel gears, two of which are shown at E and 
F. These pinions are supported on radial studs 
which project inwardly from the casing. Upon 
this casing are sprocket or bevel gear teeth 
which are driven from the engine. The teeth of 
each pinion, E and F are at all times in mesli 
with the teeth of both the bevel gears C and D 
on the axle. When the car is in operation, the 
chain or bevel drive revolves the case contain¬ 
ing the pinions, and the power is transmitted 
through the teeth of the pinions E and F to the 
teeth of the gears C and D and thence to the 
axle and wheels. So long as the vehicle travels 
in a straight line, the pinions act as stationary 
driving members, and have no occasion to re¬ 
volve, as the two halves of the axle and their 
gears are moving at equal speeds. They merely 
revolve with the frame. The same teeth of the 
bevel pinions and gears are in contact so long 
as a straight path is traversed. AVhen, however, 
the car is steered in a curve and different veloc¬ 
ities are required in the drivers and the bevel 
gears with which they are connected, the pin- 


The Automobile Handbook 


117 


ions no longer act as fixed driving members, 
but each turns upon its stud and allows the 
necessary relative motion between the two bevel 
gears, and at the same time they continually 
transmit power to the two ends of the axle be¬ 
cause they are always in mesh with each other. 
This compensating action may continue indefi¬ 
nitely through any amount of variation be¬ 
tween the driving wheel rotation, because one 



tooth of the pinions comes into play as fast as 
the preceding one disengages with the bevel 
wheels on the shaft. Fig. 53 presents a larger 
view of the bevel gear differential, the two 
gears on the rear axle being shown as secured 
to the shaft, and to a sleeve on the shaft. The 
differential employed here has three bevel pin¬ 
ions turning on radial studs, which are secured 
to the arms of a spider at their inner end. A 
differential bevel gear, all hough most extern 

































118 


The Automobile Handbook 


sively used, is open to the objection that the 
bevel gears impose an end thrust upon the two 
halves of the mainshaft on rear axle. This has 
led to the design of differentials in which only 
spur gears are used. 

Binding-Posts. Two forms of terminals or 
binding-posts are shown in Figure 54. The one 
shown at the left in the drawing is more suit¬ 
able for induction coil and dash-board connec- 



TERMINALS 


Fig. 54 

tions. A tip or connector is also shown for use 
with this terminal, which gives a far better elec¬ 
trical contact, than by the ordinary method of 
inserting the bared end of the insulated wire in 
the terminal itself. The bared end of the wire 
is sweated into the hole in the smaller portion 
of the connector as shown, the sheath or cover- 

, . ■ ...j _ , » 7 . , . 

ing of the wire going into the hole in the larger 
end of the terminal. These tips are usually 
































































The Automobile Handbook 


119 


made of brass. The right-hand view shows a 
terminal or binding-post for storage battery 
use, which is heavier and larger than the one 
shown in the left-hand view. The connector for 
use with this terminal is also shown. The wire 
is attached in the same manner as for the other 
connector. 

With storage battery terminals, corrosion is 
inevitable unless the lead and brass parts are, 
when new, taken apart, and carefully painted 
with raw linseed oil or vaseline, and screwed 
up again. The entire binding-post may be 
drenched in linseed oil, it will not only prevent 
corrosion, but, strangely enough, improve the 
electrical contact between the Avires and the 
faces of the terminals. 

Bodies. In the construction of automobile 
bodies the sills are made strong, and the super- 
Avork is rendered independent of the actual 
structural strains. Wood is generally used in 
the framing, although it is sometimes replaced 
by cast aluminum. 

When Avood is used for framing, sheet alumi¬ 
num, steel and thin layers of avooc! are em¬ 
ployed. The aluminum is laid on a form and 
beaten to the shape required for the panel. The 
steel sheets are die formed, while the wood is 
made flexible in order that it may be bent to 
its proper shape when fastened to the body. In 
order to have the car of light Aveight, all body 
builders use the lightest materials possible in 


120 


The Automobile Handbook 


the construction of that portion which lies above 
the chassis. 

When aluminum is used in the panels and 
for facings, care must be exercised to prevent 
water from creeping in between the metal and 
the framing, because water causes an electro¬ 
lytic action on the aluminum plates. To prevent 
the oxidation of sheet steel, the plates are either 
coated with aluminum or zinc, or they are given 
a. priming coat of paint on the inside. 

As a general thing, putty is not used in the 
construction of bodies, as there are few joints 
which require it. In the very best body paint¬ 
ing twenty coats are used before the paint as¬ 
sumes its proper finish. The first coat, or prim¬ 
ing coat, generally consists of pure white lead 
mixed in oil. After that the second priming coat 
is given to it, and from then on the number 
of coats of rough paint will depend upon the 
nature of the surface and the degree of finish. 
For a very fine finish, the last coats consist of 
varnish, but when wagon finish is desired, the 
last coats consist of paint. 

Finishers must take into account the fact that 
all cars are more or less abused in service, and 
it is to be expected that the magnificently 
equipped limousine will have a somewhat finer 
finish than the hard used touring car. 

Classification of Todies. Besides being 
classified according to the type of gasoline en¬ 
gine, methods of transmission, number of cyl¬ 
inders, etc., automobiles are also classified ac- 


The Automobile Handbook 


121 


cording to the type of body which is mounted 
on the chassis. While there are a considerable 
number of names which are given to the same 
types of pleasure automobiles, they may be gen¬ 
erally classified as runabouts, roadsters, toura- 
bouts, touring cars, town cars or taxicabs, lan- 
daulets, limousines and semi-limousines. Elec¬ 
tric automobiles are generally divided into 
coupes, brougham, stanhopes, runabouts, phae¬ 
tons, etc. Steam cars follow the same general 
classification as gasoline machines. Commer¬ 
cial vehicles may be classified as taxicabs, deliv¬ 
ery wagons, trucks, busses, wagonettes, ambu¬ 
lances, patrol wagons and other forms for fire 
service. 

Commercial Vehicles. In the commercial 
vehicle field steam, electric and gasoline ma¬ 
chines are used. Electric vehicles are used for 
certain purposes, from heavy trucks to light 
delivery wagons, usually only for short dis¬ 
tances; steam is used widely for all purposes, 
principally for heavy trucks, while the gasoline 
commmercial is used for trucks, business wagons 
and quick deliveries. 

The commercial vehicle may be classed as 
follows: Taxicabs, general delivery, light trucks, 
heavy trucks, coal wagons, sight-seeing cars, 
busses, ambulances and particular other types 
for special purposes. 

Since, for general purposes, the speed of com¬ 
mercial vehicles is small, they are not neces¬ 
sarily equipped with high power, as a heavy 


The Automobile Handbook 


1 99 

ALjlj 

car, which would travel at a high speed, would 
be apt to be dangerous. The speeds obtainable 
range on an average between twenty miles per 
hour for delivery wagons, to five miles per hour 
for heavy trucks. 

Limousines. With the increased use of the 
automobile for winter use has come the limou¬ 
sine with all its luxurious fittings. They are 
now heated in winter, are furnished with the 
finest and most expensive upholstery, contain 
speaking tubes, electric light, bouquet holders: 
in fact, nothing seems to be too fine for what is 
strictly the rich man's car. As they art 1 ex¬ 
tremely heavy, they are generally equipped with 
tires of large sizes, and as a general thing they 
are made with a shorter wheel base than stand¬ 
ard touring cars. 

0 A 

Roadsters and Runabouts. Runabouts as a 
class have a comparatively low-wheel base, 
limited to about ninety inches, whereas road¬ 
sters are essentially long wheel-base cars, be¬ 
tween 100 and 120 inches, because the speed at 
which they run makes this necessary. Run¬ 
abouts are designed for starting and stopping 
quickly, whereas roadsters, as their name im¬ 
plies, are intended to be used on all road con¬ 
ditions. 

Taxicabs. The general considerations in¬ 
volved in the design of this type of vehicle are 
somewdiat similar to those governing the design 
of a low-powered touring or town car, but a 
number of minor requirements, not usually ac- 


The Automobile Handbook 


m 

corded mucli attention in touring car design, 
attain considerable importance in the motor 
cab. Economy of operation is perhaps the most 
salient of these, while low speed and short turn¬ 
ing radius are next in importance in their effect 
on design. 

A motor of from twelve to fifteen horsepower, 
at a speed of 1,000 to 1,200 revolutions per 
minute, is ample for cab service-, although some 
taxicabs are built with only eight or ten horse¬ 
power. Both the two-cycle and four-cycle types 
of motors are extensively used. 

Touring Cars. These types of cars may be 
divided into two classes, light touring cars and 
standard touring cars. Light touring cars gen¬ 
erally have a wheel base of about 110 inches, 
and seat five persons comfortably. Motors are 
generally of the four-cylinder type, rated at 
from twenty to thirty horsepower. The car 
weighs between 2,200 and 2,500 pounds. The 
light touring car differs in no way from the 
standard touring car except that it is lighter, 
has less power and is geared to speed of about 
two-thirds of the speed of the standard touring 
car. 

The standard touring cars are generally de¬ 
signed for seven persons. The motors are four 
or six-cylinder types, and the power is usually 
well above thirty horsepower. 

Brakes. A brake is a mechanism which is 
a necessary part of the machinery of an auto¬ 
mobile and enables the operator by exerting a 
slight amount of force on a lever to reduce the 


124 


The Automobile Handbook 








































The Automobile Handbook 


125 


momentum of the moving car. Brakes used on 
automobiles may be divided into three classes: 
Hub or rear wheel brakes, transmission and 
differential gear brakes. Brakes have also been 
applied to the tires of the rear wheels, but 
have proved unsatisfactory and have been aban¬ 
doned. The forms of brakes in use are single, 
or double-acting, foot or hand operated, and of 
the band, block or expanding ring types. 

Figure 55, at A, B and C, shows three forms 
of the simplest type of single-acting band-brake. 
This type of brake can only be operated success¬ 
fully with the brake wheel running in one 
direction only, which is indicated by the arrows 
in the drawing. If the brakes be operated in 
the reverse direction to that indicated bv the 
arrows the result will be to jerk the lever or 
pedal out of the control of the operator of the 
car. 

The three forms of band-brakes shown at A, 
B and C are all of the same principle, the differ¬ 
ence being in the location of the fixed end of 
the brake-band and the shape of the operating 
lever. Type D is a form of double acting block- 
brake, which is designed with a view to elimi¬ 
nate any strain or side thrust upon the shaft of 
the brake wheel which may be caused by the 
braking action of the device. Types E, G and 
H are three types of double acting band-brakes, 
in which the brake may be applied with the 
brake wheel running in either direction. 

Type F is a form of double acting block-brake, 



126 


The Automobile Handbook 


in which the right hand ends of the brake-shoe 
arms are pivoted to stationary supports, and 
the left hand ends connected together by means 
of a link and bell-crank lever as shown in the 
drawing. 



Fig. 56 

In Figure 56 a form of double acting block- 
brake I is shown, which is extremely powerful 
on account of its peculiar construction, in that 
is has a double leverage upon the brake wheel, 
which may be readily seen by reference to the 
drawing. Types J and K are of the form known 


































The Automobile Handbook 


127 


as internal brakes and of the expanding ring 
type, the brakes operating upon the inner sur¬ 
face or periphery of the brake wheel, instead 
of the outside. They are known as hub brakes, 
being usually attached to the hubs of the rear 
wheels of the car. Type L shows a form of 
block-brake in which the pivoted brake arms 
are drawn together by the eccentric located on 
the brake lever shaft. When the lever is re¬ 



leased the brake-shoe arms are forced apart by 
the action of the coil spring between the upper 
ends of the arms. 

Expanding Brake. In the internally expand¬ 
ing brake, Figure 57, a hollow metal drum or 
pulley D is carried upon some, continuously 
revolving portion of the car mechanism, and 
within this drum are supported two metallic 
shoes B B, which conform in shape to the inside 










128 


The Automobile Handbook 


surface of the drum by means of a spring, S S. 
The shoes are capable of being strongly pressed 
against the revolving inner surface of the drum 
by means of a cam or toggle arrangement, T, 
operated through a wire rope or metal rod, R, 
from the operator’s lever or pedal. It is im¬ 
portant that brakes of both these types should 
have their bands or shoes so arranged that an 
equal frictional effect is produced upon their 
drums for a given force applied by the operator, 



whether the vehicle is running forward or back¬ 
ward. A brake so arranged is said to be double 
acting. Another type of expanding brake is 
shown in Figure 58, where D is the brake drum ; 
8 S, the brake shoes; T, the toggle arrangement 
which connects with the brake lever, and N is 
a nut which is used for adjusting the movement 
of the brake shoes. 

Advantages of the Expanding Brake. The 
expanding brake is coming more and more 










The Automobile Handbook 


129 


into general use, and is taking the place of 
the contracting brake in many cases, although 
the latter is still being used extensively as an 
emergency brake. 

The advantages of the expanding brake are: 
(1) it is less liable to drag upon the drum; (2) 
it is easily made double acting; (3) it has more 
braking power for a given pressure; (4) the 
friction surfaces are better protected from mud 
and grit. 

Differential Brakes. This type of brake 
is arranged to act upon a drum forming part 
of the frame that carries the sprocket and dif¬ 
ferential pinions. It usually consists of two 
drums, one of which is fastened to each of the 
large gears of the differentials. The straps and 
bands encircling these drums are tightened by 
pedal, or lever in the usual manner. The dis¬ 
advantage of this type of brake is, that it can 
only act equally upon the two drivers when 
neither wheel slips. Should one wheel slip, the 
application of this brake would cause skidding. 

Brake Linings. For expanding brakes, metal 
shoes have become standard, owing to the prac¬ 
ticability of maintaining proper lubrication be¬ 
tween the frictional surfaces. In external 
brakes the metal band is provided with some 
form of nonmetallic lining that forms the brak¬ 
ing surface applied to the drum. The reason 
for this is that it is practically impossible to 
properly lubricate an external brake. Various 
kinds of material, viz., leather fabric, asbestos, 


130 


The Automobile Handbook 


vulcanized fibre and camel’s hair belting, are 
used for lining external brake bands. A ma¬ 
terial which is used for this purpose must have 
great resisting powers, a constant co-efficient 
of friction, even in the presence of oil and 
water, and it must have the ability to resist 
the influence of heat due to the brake’s action. 
In practice it has been found that leather lined 
brakes burn out, and fibre linings become brittle 
and cannot be depended upon, so that inorganic 
materials, which cannot be carbonized, such as 
asbestos fibre, are widely used. Asbestos fibre 
may be readily woven into a fabric which an¬ 
swers this requirement, but when used by itself 
its strength is not sufficient. When, however, 
it is woven over a metal wire gauze foundation 
it appears to have the necessary stability to 
withstand very severe service, and this is the 
method employed in manufacturing the incom¬ 
bustible brake linings which are being used. 

Fibre comes in two forms, hard and flexible. 
Both are formed from vegetable fibre which lias 
been put through a chemical treatment, by pres¬ 
sure, so that it will not be soluble in ordinary 
solvents, such as ammonia, alcohol, ether, naph¬ 
tha, benzine, kerosene and oils. It will swell 
when placed in either hot or cold water, but 
when dried out the fibre returns to its original 
condition. In service it is found very satisfac¬ 
tory as far as wear is concerned, but is not 
very reliable if subjected to heat. 

Leather forms an excellent lining for brakes 


The Automobile Handbook 


131 


of large proportions, but has its disadvantages. 
It must be kept moist or it will char, and the 
wear of the surface will be excessive, becoming 
brittle and breaking off. The kind generally 
used is oak tanned leather, which has good 
wearing qualities, as well as a very good co¬ 
efficient of friction when used in connection 
with a metallic drum. It is easily applied, and 
is comparatively cheap. 

Textile linings are very popular and are 
made in a number of different manners. Or¬ 
dinary cotton lining is made from four to ten 
thicknesses of cotton duck stitched together, 
and is very strong. It is waterproof and 
cheaper than leather, is easier of application 
than either leather or fibre, and has a very sat¬ 
isfactory co-efficient of friction. It has an ad¬ 
vantage of not charring so readily, and it is 
claimed that its wearing qualities are better. 
Camel’s hair belting is very suitable, as are also 
fabrics of which asbestos is the main element, 
which have great resistance to heat and good 
wearing qualities. 

Cork is the bark of the cork tree, and is the 
lightest known solid. Its weight is one-eleventh 
of aluminum, and one-thirtieth of cast-iron. It 
has a very high co-efficient of friction, and is 
not affected by many of the conditions which 
seriously impair the efficiency of other sub¬ 
stances. 

Cork possesses qualities which distinguish it 
from all other solids, namely, its power of alter- 


132 


The Automobile Handbook 


ing its volume to a very marked degree in con¬ 
sequence of a change of pressure. It consists, 
practically of an aggregation of minute air ves¬ 
sels, having thin, water-tight, and very strong 
walls, hence, if compressed, the resistance to 
compression rises in a manner more like the re¬ 
sistance of a gas, for instance, than to that of 
an elastic solid, such as a spring. The elasticity 
of cork has a wide range and is very persistent. 
It is this elasticity which makes it valuable when 
used as an insert in a metal shoe. Cork is of 
rather a brittle nature, though extremely strong, 
and for that reason it cannot be used in the form 
of a lining or facing. The method of applica- 
cation is to insert corks in holes in the brake 
provided for the purpose. Cork is not particu¬ 
larly affected by heat or oil, and will largely in¬ 
crease the efficiency in any application to a 
brake or clutch. 

Where metal-to-metal surfaces, with or with¬ 
out cork inserts, are used, the surfaces are usu¬ 
ally of different materials. The most common 
material for drums in all cases is steel, but that 
of shoes is either malleable cast iron, brass or a 
bronze. Different metals make a better wear¬ 
ing surface, and some combinations will have a 
higher degree of friction adhesion than others. 

In the selection of material for brake linings, 
the co-efficient of friction is an important factor 
to be considered. Table 9 gives the relative 
values existing in combinations of different 
materials. 


The Automobile Handbook 


133 


TABLE 9. 

Co-efficient 


Material—• of friction 

Metal to Wood . 0.25 to 0.50 

Metal to Fibre . 0.27 to 0.00 

Metal to Leather . 0.30 to 0.6O 

Metal to Metal . 0.15 to 0.30 

Metal to Cork. 0.36 to 0.65 


Equalizers. In connection with all brakes 
which are used in pairs, some method is used to 
equalize the pressure of the brake handle or foot 
pedal so that the same pressure will be applied 



Fig. 59 

Floating Lever Type of Equalizer 


to both brakes. If the power is not equally ap¬ 
plied to each brake, side slip or “skidding” will 
result. 

The different methods of equalizing brakes are 
shown in Figs. 59, 60, 61 and 62, the majority of 
cars using what is known as the floating lever 
type, the cable arrangement being used only on 
several makes of cars. The floating lever type 














































134 The Automobile Handbook 

of equalizer is illustrated in Fig. 59. L is the 
floating lever, connected at its central point to 
the brake lever, or pedal by means of rod R. 
The ends of lever L‘ are connected to the brakes 
B, B, by means of the brake rods C and I). 
When rod R is drawn forward, lever L draws 
rods C and D forward thus giving an equal pres¬ 
sure on the hub brakes. 

Fig. 60 shows another type of floating lever 
equalizer. Shaft S connects to the brakes by 


5 

. \ 


Wg>=^crD 


Q) -A—» 

.S-- 


l 



Fig. 60 

Floating Lever Equalizer 


means of rocker arms located just outside the 
frame. Two rocker arms, C and D are con¬ 
nected to shaft S, and to the equalizing lever L 
by means of rods E and F. In some cases the 
equalizing lever is located outside of the frame. 
It then takes the form shown in Fig. 61, in 
which L is the lever that equalizes the pressure 
on both brakes connected to shaft S. Fig. 62 
shows the arrangement of the cord equalizer. 
Shaft S is connected to the two brakes, one at 





















The Automobile Handbook 


135 


each end, and it has two rockers, or cranks E 
and F attached to it. Parallel to S is another 
shaft C, which carries a grooved roller R. A 
cable is connected to crank E, carried over R, 
and then passing back, is connected to crank F. 
When R is moved in the direction of the arrow, 
by the brake lever, the cord distributes the ten¬ 
sion between E and F, and as a consequence the 
brake also. This type is much cheaper than 
the others, but it requires more care and atten¬ 
tion. 



S’prag Brake. Sprags are sometimes used on 
large touring cars. A sprag is merely a strong 
steel bar, connected at its forward end to some 
point of the under part of the frame, while its 
rear end is pointed, and hangs suspended by a 
chain by means of which it may be dropped to 
the ground in case of emergency, thus prevent¬ 
ing the car from running backwards down hills. 
A good plan is to allow them to trail on tbe 
ground while ascending dangerous hills, and 






















136 


The Automobile Handbook 


thus insure their immediate action in case of 
accident. 

A sprag’ sometimes takes the form of a ratchet 
wheel and pawl arranged either on the rear 
axle, on the differential or within the change- 
speed gear box, so that backward motion of the 
car is impossible when it is set in action. Ratchet 
sprags may be arranged to go into action when 
set by the driver, but a better plan is to have 



them so arranged that they will always prevent 
the backward movement of the car, except when 
the reverse is thrown in. 

Tendencies of Brake Construction. The 
tendency of brake construction is toward dou¬ 
ble brakes on the rear wheels, some cars having 
two flanges with two expanding brakes, others 
having one flange with a contracting band on 
the outside, and an expanding band within. The 























The Automobile Handbook 


137 


only exception to these types of brakes is in the 
use of cone brakes, which, however, is not con¬ 
sidered seriously as a brake which must meet 
all requirements. The practice of using a brake 
on the propeller shaft is less usual. 

Water-cooled brakes are used on several 
cars, and in others the brake flange has radiating* 
flanges around it to permit cooling by air. The , 
practice of interconnecting brake and clutch is 
still popular, although some cars have this in¬ 
terconnection only with the emergency brake. 

Brakes, Proper Use of. Next to the motive 
power in importance come the brakes. There 
are a number of points regarding brakes that 
every autoist should know and remember. First 
and most important is the fact that brakes vary 
in their effectiveness, and that freedom from dis¬ 
aster depends upon the brakes being kept in 
good condition and properly adjusted. Second, 
while a brake may be perfectly satisfactory for 
slowing down, it by no means follows that it will 
bring a car to a stop as it should, nor hold the 
car from going backward. Third, brakes 
should be tested frequently with the car in 
motion, the pedal or hand lever being applied 
until the car slows down, or stops. The distance 
covered in making this test should be noted, 
and a greater distance allowed in making stops 
on the road. 

In applying brakes, the application should be 
gradual, reducing the speed of the car as quickly 
as possible without locking the wheels. As long 


138 


The Automobile Handbook 


as the tires retain their grip on the road, the 
powerful retarding action of the brake contin¬ 
ues, but when the wheels are locked the brakes 
have little or no effect, and the car will either 
slide along, or skid, in either case being be¬ 
yond the control of the driver. Should the 
wheels become locked while descending a hill, 
the brakes should be released until the wheels 
are again revolving, and then reapplied gradu¬ 
ally, until they act satisfactorily. 

Brakes should be examined at regular in¬ 
tervals in order to ascertain if the lining is in 
good condition. If worn, the old lining should 
be replaced with new. If the brakes are of the 
internal-expanding type, the shoes may have 
become worn, in which case they should be re¬ 
newed. Toggle joints and adjusting nuts 
should be inspected, and any looseness taken up. 
Brakes should be adjusted on the road, as any 
improper adjustment of the equalizer bar will 
have a strong tendency to make the car skid. 
Both brakes should be adjusted alike, that the 
braking force applied by the equalizer may be 
transmitted to the wheels equally. 

Brass—How to Paint. First apply a thin 
even coat of shellac. When this is dry, the paint 
may be applied in any number of coats desired. 
The shellac may be colored before applying, 
and thus lessen the number of coats of paint 
needed. In this way the job can be completed 
with one or two coats of paint, and as the shel¬ 
lac will stand a much higher temperature than 


The Automobile Handbook 


139 


will ever obtain in a radiator, it will prevent the 
peeling* off of the paint. 

Brazing. Many workmen labor under the im¬ 
pression that a brazing job cannot be done un¬ 
less the parts are a loose tit, in order, as they 
say, to allow the brazing material to enter and 
form a bond. The result is, when they do the 
work, the parts are a very loose tit, with accen¬ 
tuated shearing tendencies in the section of the 
bra sing material, and if the brazing happens to 
be poorly done, the result is anything but good, 
since, in the absence of brazing, there is not 
even a good mechanical bond. 

A good mechanical bond is possible to procure 
without, in any way, interfering with the braz¬ 
ing process, since the parts, if they are well 
fluxed, will take a coat of brazing material, even 
when the recess is but a thousandth or two. In 
brazing, if the work is to be up to a sufficient 
standard to use in steering gear, it is necessary 
to clean and brighten the surfaces in a most 
thorough manner. This will best follow by me¬ 
chanical scraping rather than by dipping in 
some corroding material. Dipping may be of 
value as a preliminary, but a file, and scraper, 
in the hands of a man of competence, will go a 
long ways toward success. 

When the parts are well brightened, and the 
grease is thoroughly removed, by the use of 
soda water, benzine, or equally good solvents, 
it remains to flux the parts with borax, and 
then apply the heat, either by a forge or from a 


140 


The Automobile Handbook 


Bunsen burner; if fire brick, or clay, is used to 
build up around the parts, the heating process 
will be attended with less difficulty, and the work 
will be better at the finish. A rather hard braz¬ 
ing material may be used. This may be pur¬ 
chased ready for use, and there is no reason at 
all why a motorist of even slight skill cannot 
make a good job of brazing. 

Break Downs, and Their Remedies. 

Chain Broken. In case a chain should break, 
and there are no spare links available, the car 
may be driven by the other chain, provided tin- 
idle sprocket is secured so that it cannot re¬ 
volve. An easy way to do this is as follows: 
Pass one end of the chain around the sprocket, 
secure the end link to the chain with wire, and 
attach the other end of the chain to some part 
of the car, as a running board bracket. 

On shaft driven cars the universal joint pins 
sometimes work loose, and drop out. In such 
cases a temporary pin can be made from a bunch 
of wire, or by a small chisel held in place by 
wires, or twine. 

Circulating Pump Leakage. Leakage of 
the water circulating pump occurs usually 
where the cover joins the pump body by means 
of a ground joint. A gasket of stiff paper 
dipped in lubricating oil inserted between the 
cover and the body will remedy this, the gasket 
being easily formed with the pocket knife. As¬ 
bestos cord is better than paper when treated 
with vaseline and graphite, but few autoists 


The Automobile Handbook 


141 


carry it. For leakage around the pump spindle 
the cord can be used, pushing it in with a piece 
of strip brass or other soft metal so as to avoid 
scratching the shaft. If no asbestos cord is at 
hand one of the strands of a piece of hemp rope 
treated with tallow will also answer. 

Cranking with Safety. The principle in¬ 
volved in safely cranking an engine is, to get 
the explosion at the moment the crank is pull¬ 
ing on the fingers, so that if the kick comes the 
force will simply pull the handle out of the 
grasp, instead of being expended against the 
body weight and applied force. Do not attempt 
to turn the crank all the way around; adjust it 
to start against the compression, then give a 
quick pull upward. 

Differential Casing. In cases of emergency 
where oil or grease cannot be obtained for fill¬ 
ing the differential casing, beeswax may be 
used as a substitute. 

Dry Cells for Ignition. Dry cells will give 
very satisfactory ignition for a four cylinder 
motor by using four sets of four cells each, con¬ 
nected in series multiple so as to get a voltage 
of only six colts. By having the vibration re¬ 
spond quickly to the pull of the magnet in the 
coil, battery consumption will be greatly les¬ 
sened. The slightest current should separate 
the contact points. 

Gasoline Pipe Broken. When the gasoline 
pipe breaks, a short piece of rubber tubing 
forced over the broken ends will do for a short 


142 


The Automobile Handbook 


time, but as gasoline attacks the rubber, too 
much dependence should not be put on it, and 
the pipe should be brazed at the nearest shop. 
If the hole is only a small one a piece of soap 
squeezed in and held in place by a soaped rag 
and string will serve if gravity feed is used. 
For pressure tanks a piece of rubber tubing 
split lengthwise and well soaped will tempora- 



Fig. 63 

False Teetli, Permanent Repair 


rily stop the hole, if wired tightly around the 
pipe, but the pressure must be kept low, other¬ 
wise the rubber tubing will be loosened and the 
leaking commence again. 

A leak is sometimes hard to locate, but if the 
pipe is rubbed with soap suds, and then blown 
through, the leak will be located by the bubbles. 

Gear Teeth Broken. If several teeth are 






The Automobile Handbook 


143 


wholly, or partly broken they may be repaired 
in the following manner; referring to Fig. 63: 
Shape out a dovetail recess across the face of 
the wheel, cast or shape up a brass, bronze, or 
steel segment and dovetail it in, driving it tight 
from one side, and securing it with screws. 
Then file the teeth to a template made from the 
standing teeth of the wheel. For a single tooth 
proceed in the same way, no screws being neces¬ 
sary if properly fitted and the ends peened over 
with a hammer; or, file down the broken tooth 
flush with the bottom, drill and tap two or 
three holes, according to the width of the wheel, 
screw in capscrews and trim with a file. It 
might be well to add, when removing a timing 
gear for repairs, or any other purpose, care 
should be taken to see that it, and the gears 
with which it meshes, are plainly marked. 

Miss Fire Cylinder. Should one of the cyl¬ 
inders miss some of its regular explosions at 
intervals when under a load, it may be located 
bv stopping the engine, and touching each cyl¬ 
inder with the business end of an unlighted 
match. The cylinders that have been doing 
their regular work will be hot enough to ignite 
the match, while the missing cylinder will not. 

Nuts and Screws —TIow to Loosen. Refrac¬ 
tory nuts may be loosened by heating, by means 
of a red-hot piece of iron held on or near them 
for a few minutes. This will expand the nuts 
and they will then come off readily. When a 
screw cannot be readily loosened with a screw- 


144 The Automobile Handbook 

driver, the latter should be pressed hard into 
the slot, while a helper applies a monkey wrench 
to the flat part of the blade. A tight radiator 
cap can be moved by winding a quantity of 
twine, or cloth tightly around it. 

Priming. If a motor does not start readily, 
due to not getting a rich enough mixture at 
slow speed of cranking, tie a small bunch of 
waste with a wire close to the air intake of the 



Fig. 64 

Section of Radiator Showing Washers Held by W ires on 

Stick, To Stop Leak 

carbureter, then prime by saturating the waste 
with gasoline. The added vapor will make 
starting easy. 

Radiator Leaking. In case a “honeycomb” 
radiator starts leaking at the end of a cell, and 
there is no radiator plug at hand, a substitute 
may be made by passing a long bolt of small 
diameter through the defective cell and fitting 
each end of the bolt with washers made of 
leather, or rubber backed with iron washers or 




















The Automobile Handbook 


145 


metal strips, and then screwing down the nut 
until the leak is stopped. If a bolt cannot he 
obtained a small piece of wood may be whittled 
down to take its place, and the washers secured 
by means of copper wire as shown in Fig. 64. 



If a leak occurs inside one of the cells, a square 
peg cut from soft wood, and covered with a 
piece of thin cloth smeared with white lead can 
he used! as a plug. • Only a moderate force 
should he used in these methods, as the tubes 






































146 


The Automobile Handbook 


are easily buckled. Leaks in gilled radiators 
may be stopped by applying a rubber patch held 
in place by tire-tape and wire. 

Rods or Links Broken. The repair of a 
broken link in the steering gear can be effected 
by placing the broken ends together and fasten- 



Fig. 66 

Valve Spring Strengthened by Inserting Metal Strips 

ing a rod or a piece of gaspipe against the link, 
winding the wire the entire length of the rod. 
If two hand vises can be obtained they can be 
attached as shown in Fig. 65. The rod is tied 
to the joined ends of the link with wire, and the 
hand vises screwed down on both link and rod. 
Anything but slow running with either of these 























The Automobile Handbook 


147 


repairs is out of the question. Any other rod 
can be similarly repaired provided there is room 
for the pipe or the vises alongside of it. Wire 
cable can be substituted for brake rods, but the 
brake must be kept clear of the drum by some 
means when not in use. 

Squeaking Springs. A frequent source of an¬ 
noyance is the squeaking caused by the leaves of 
the springs having become dry from want of lu¬ 
brication. When such is the case, jack up the 



Fig. 67 

Method of Testing Valve Springs 


axle until the wheels are clear of the ground, 
and the springs quite flat. Then with a thin 
cold chisel, or a large screwdriver, gently force 
the leaves apart, one by one, and spread a mix¬ 
ture of vaseline, oil and graphite between them, 
using an old table knife or thin wooden paddle 
for the purpose. Where parts cannot be 
reached in this way, oil should be squirted in, 
and if necessary the leaf clips may be removed 
to allow of this being done. 

Trembler Blades Broken. Corset steels may 







148 


The Automobile Handbook 


be used as blades for trembler coils, by cutting 
them to the proper length, and riveting the 
platinum button from the broken blade through 
the hole which is punched near the end. After 
making the holes for the retaining screw, the 
blade is complete. A piece of the main spring 
of a clock will also make a good blade. 

Twine is Useful in Breakdowns. Autoists 
should always carry 15 or 20 yards of strong 



Fig. GS 

Corset Steels Used As Impromptu Valve Springs 


twine in their kit, as it may be put to various 
uses about the car, such as reinforcing weak 
spots in tires, protecting chafed wires, and bind¬ 
ing together split sections of the steering wheel. 
Twine may also be used as a substitute in the 
absence of a lock washer, by forming a loop 
slightly larger than the diameter of the nut, 
and then wrapping twine around this loop, 
forming a “grommet,” as sailors call it. When 






























The Automobile Handbook 


149 


the nut is screwed down upon the grommet it 
will be held as firmly as if fitted with a nut- 
lock, and will stay tight until the twine rots. 

Valve Springs Weak. Mechanically oper¬ 
ated inlet valves have generally superseded 
those of the automatic type, except for two- 
cylinder opposed motors fitted in light run¬ 
abouts and buggies. When the springs on these 
valves become weak, which they are liable to 
do, they may be strengthened by inserting thin 
strips of brass, or other metal between the spring 
and the spider of the valve cage, as shown in 
Fig. 66. A spring thus strengthened may be 
tested against another spring known to be right, 
by placing the ends of the stems together as in 
Fig. 67 and pressing the cages toward each 
other. The metal liners can then be put in place 
until the valves both unseat equally, indicating 
that the springs are of equal power. If a spring 
is broken, pieces of corset steel may be substitu¬ 
ted for it, one end of each steel being notched to 
straddle the spider arm, while the other end is 
secured to the collar wedge by a wire passed 
through a hole near the end as shown in Fig. 68. 
Even if the power of the steels is not equal to 
that of the regular spring, the motor will run 
well enough to bring the car home, or to a repair 
shop.. 

Various Causes of Break Downs. Any one 
of the following troubles may be the cause of a 
motor stopping or not working properly: 

Soot or grease on the spark plug. 


150 


The Automobile Handbook 


Defective insulation of the spark plug. 

Points of the spark plug too far apart. 
Contacts of the coil vibrator badly corroded. 
Broken wires or loose battery terminals. 
Leaky admission or exhaust-valve. 

Seized piston or bearing. 

Broken valve-stem or valve-spring. 

Batteries exhausted. 



Defective spark coil. 

Poor contact at the commutator. 

Defective insulation of the secondary wires. 
Broken piston ring. 

Stuck piston. 

Defective packing. 

Brock Carbureter. Fig. 69 is a sectional 
view of the Brock Carbureter. The float cham¬ 
ber is concentric with the mixing chamber, and 



























The Automobile Handbook 


151 


the gasoline enters the mixing chamber through 
an annular valve instead of through a central 
spray nozzle. At each suction of the engine a 
thin film of gasoline moistens the inside of the 
outer stand pipe, and is simultaneously wiped 
off by the sheet of incoming air. The central 
standpipe forms a supplementary air passage, 
which is controlled by a spring-pressed valve at 
the bottom, which latter is adjustable from the 
outside. Air enters through a ring opening A, 
and flowing downward, as indicated by the ar¬ 
rows, passes a slit opening IT in the inner side 
of the float chamber wall, through which the 
gasoline emerges. Laden with gasoline, the air 
continues its downward path and finally exits 
through the circular opening K. The size of the 
gasoline opening II is regulated by screwing up 
or down the top piece C, or cover of the float 
chamber. The float G maintains a level ap¬ 
proximately one-sixteenth inch above the escape 
slit IT, and in adjusting or getting the correct 
size of this opening the proper method is to 
screw C down until it seats firmly at H, and 
then unscrew it about one-eighth of a turn. 

The edge of cap C being serrated and marked 
facilitates this work. All of the air needed 
cannot enter by the ring opening A, conse¬ 
quently it finds entrance through the vertical 
pipe B, which is located centrally in the car¬ 
bureter. The bottom of this pipe is guarded 
by a spring-controlled poppet valve E, with ad¬ 
justing screw F. 


152 


The Automobile Handbook 


The needle valve for controlling the entrance 
of gasoline into the float chamber is located in 
an enlargement at the side of the float chamber, 
and the valve is operated by means of a short 
lever pivoted into the side of the chamber, so 



Fig. 70 

Left Side of Motor Showing Intake and Exhaust 

that a very short arm acts upon the needle valve, 
and a much longer arm on the float, thereby 
causing a very delicate float operation and con¬ 
trol. Viewed structurally the bottom part of 
the float chamber B, and the part uniting the 
induction pipe to the motor are cast integrally, 





The Automobile Handbook 


153 



thereby leaving the top C free for adjusting the 
flow of gasoline, or for removal in case of 
cleaning. 

Buick Motor. In the Buick Motor the cylin¬ 
ders are cast in pairs, with ample water jacket 
space on sides and heads. An important feature 


Fig. 71 

Right Side of Motor Showing Valve Action 

in connection with this motor is, what the build¬ 
ers term the “ valve-in-the-head” construction, 
that is, both intake and exhaust valves are located 
in the cylinder heads, thus confining to a mini¬ 
mum the volume of burned gases remaining in 
the cylinders after each explosion, to mix with 




154 


The Automobile Handbook 


the incoming new gas. It is also claimed by the 
makers that owing to the fact that the power 
created upon ignition is directly applied to the 
piston head, the efficiency of the motor is thereby 
increased. Figures 70 and 71 show respectively 



Fig. 72 
Cylinders 

the left and the right side of the motor, while 
Fig. 72 shows a pair of cylinders with the parts 
dis-assembled. 

Water circulation through jackets and radi¬ 
ator is produced by a gear pump having capac- 










The Automobile Handbook 


155 


ity sufficient to maintain a fast and free circula¬ 
tion. The cam shaft and magneto gears are en¬ 
closed, and run in oil. A single cam shaft serves 
to operate both the intake and exhaust valves. 
The current for ignition is now supplied by a 
Remy magneto, while a reserve set of dry cells 
supplies the primary current for starting. Both 
the magneto and batterv current travel the same 
course, after reaching the coil box, the circuit 
breaker, and distributor section of the magneto 
being used in either case. The preceding de¬ 
scription refers principally to models 16 and 17. 
Another important feature in connection with 
this motor is that it is self-starting, the connec¬ 
tions being such that by turning the switch over 
to the battery, and pushing and releasing the 
starting button, the primary current from the 
battery is sent through the coil, no matter 
whether contact is being made by the circuit 
breaker or not. In other words, it is possible 
to get a spark at any place in the cycle of the 
motor. 

The transmission is of the sliding gear, selec¬ 
tive type and is very compact and strong. Three 
speeds forward and one reverse are provided. 
The shifting of the gears is effected quietly, 
quickly and positively. All parts are made of 
the best nickel steel, specially treated, rendering 
them capable of resisting friction and wear, and 
at the same time so tough as to stand the tre¬ 
mendous strain being put upon them without 
breaking. 


156 


The Automobile Handbook 



uoth spark and throttle levers are located on 
steering wheel, and work on an immovable 
sector. 


Wiring Diagram of a No. 10 Buiek Motor 





















































































The Automobile Handbook 


157 


Speed changes are effected by means of a 
hand lever, three speeds forward and one re¬ 
verse being provided. The emergency brake is 
applied b> the emergency brake lever. 

Foot pedals operate the clnteh release and 
service brake. 

The emergency brakes are internal expanding 
on hub and act upon 14-inch drums. These, to- 
gether with the service-brake, are sufficient for 
any grade which the car can climb. 

Fig. 73 shows a wiring diagram of a No. 10 
Buick Motor, and as the coil terminals and plugs 
are all numbered, any specific directions as to 
methods of wiring are unnecessary. On the 
flywheel is a line marked “Center,” and 1 y 2 
inch from this is another line marked “Exhaust 
Closes, 7 ’ and approximately % inch from this 
is a third mark designated “Intake Opens.’ 7 
To time the exhaust valves, bring the flywheel 
so that the “center” mark is up, then rotating 
it until the “exhaust closes” mark reaches the 
point. This would give the timing for the ex¬ 
haust valve for say No. 1 cylinder. Bringing 
the flywheel a complete revolution to this mark 
would give the timing for No. 3 cylinder, and 

two successive revolutions would give the tim- 

/ 

ing for cylinders 4 and 2. This would finish 
the timing of the exhaust valves. The timing 
on the intakes is identical, excepting that the 
flywheel is stopped on each revolution at the 
point marked “intake opens.” 


158 


The Automobile Handbook 


Buffalo Carburetor. Fig. 74 shows two sec¬ 
tional views of the Buffalo Carburetor, in which 
springs and air adjustments are not used, all 
changes in admission or mixture controls being 
positive on the command of the operator. Ad¬ 
mission of the gasoline is regulated by a cork 
float which operates a needle valve by means of 
the rocker arm A having a slot in one end for 

i 


Fig. 74 

Buffalo Carburetor 

union with the float stem, and a pivoted connec¬ 
tion at the other end to the top of the valve 
stem. The mixing chamber is a vertical air 
passage at one side of the float chamber, and 
air entering through a horizontal opening B at 
its base mixes with the gasoline at a point mid¬ 
way of the height of the chamber, and thence 
passes through the horizontal opening C at the 
top. The entrance of the air is guarded by a 







































The Automobile Handbook 


159 


starting valve D, the escape of the mixture be¬ 
ing regulated by the throttle E. The mixing of 
gasoline and air is accomplished by the revolv¬ 
ing cone valve F. The gasoline enters at the 
apex of the valve, under regulation of needle 
valve C, and rises through the bent pipes H. H, 
having their openings in air ports which may 
be regulated, in cone valve F. The velocity of 
the air passing the nozzles may thus be main¬ 
tained constant regardless of the speed of the 
motor, the valve being interconnected wi-th the 
throttle, the interconnection for this purpose 
being adjustable. 

Brush Carbureter. In the Brush carbureter 
a diaphragm pump deposits the gasoline into a 
chamber that resembles a float chamber, minus 
the float. The pump at one end connects with 
the motor crank case, and at the other side with 
the gasoline tank, there being interposed two 
ball valves, one in the tube between the tank 
and pump, and the other between the pump and 
the float chamber. On the upstroke of the pis¬ 
ton, gasoline is drawn from the tank, and on 
the down stroke it is forced into the chamber. 
An overflow pipe leads from the chamber back 
to the tank, for use when the pump delivers 
more gasoline than the motor requires. From 
the chamber the gasoline rises to a level in a 
standpipe or spraying nozzle, past which an air 
current flows taking up the fluid. A spring 
controlled auxiliary air valve is used on this 
earburetor. 


160 


The Automobile Handbook 


Cadillac Carbureter. This carbureter as 
used on four cylinder cars is of the float feed 
•type of the usual construction. The type used 
on single cylinder cars is of a different construc¬ 
tion, in which the gasoline is dropped by grav¬ 
ity into a wire mesh, while the air which passes 
in through the intake tube evaporates the liquid 
by passing through the film of gasoline formed 
on the wire mesh. The mixture is then drawn 
up and through the inlet valve into the combus¬ 
tion chamber. 

Camshaft. Fig. 75 is a sectional view of a mo¬ 
tor cylinder and illustrates the principle and ac¬ 
tion of the camshaft. In many motors one cam¬ 
shaft serves to open both intake and exhaust 
valves, while in other motors there is a cam-shaft 
for each set of valves. Besides opening the valves, 
the cams determine the length of time the valves 
remain open, also the speed with which it opens 
and closes. Referring to Fig. 75, A is the crank¬ 
shaft, P the piston, D is the cam-shaft which 
carries the cam E. The speed of the cam-shaft 
depends upon the type of engine. The one 
shown in Fig. 75 is driven at half the speed of 
the crank-shaft through the gear wheels B and 
C, B being one half the size of C. H is the 
valve to be opened, which in opening must be 
lifted off its seat. This is done when the cam 
E revolves and raises the roller G on the lower 
end of lifter rod F which extends upward rest¬ 
ing against the lower end of the stem of valve 


The Automobile Handbook 161 

H, although between the two rods, or rather at 
their point of contact are nut and lock-nut L, 



for adjusting the length of F when timing the 
valve. K is a spiral spring, the function of 

























162 


The Automobile Handbook 


which is to close the valve, after the cam E trav¬ 
els around and allows G to drop. Directly 
above valve H is the intake valve M, which in 
this case opens downward. This valve opens 
automatically, due to the suction of the piston 
in moving downwards on the intake stroke, but 
is kept closed during the compression and ex¬ 
haust strokes of the piston, by the pressure in 
the cylinder. 

Car Inspection. Most autoists are content to 
make all their inspection of the car and its mech¬ 
anism from above, and rarely give more than a 
casual glance below the frame except when 
trouble occurs. On cars fitted with pressure-feed 
on the gasoline, the piping should be frequently 
inspected, on account of the danger from fuel 
leakage. Such inspections should be made 
when the motor is stopped, and the pressure still 
turned on. - The tank should be gone over for 
leaks arising through the opening of its seams 
from vibration, or the loosening of the union 
connecting the fuel lead with the tank. The 
lead and its connection to the carbureter should 
also be examined for leaks and abrasions due to 
rubbing against other parts of the mechanism. 
If any such are found they should be immedi- 
diately repaired. Twine, tire tape, or rubber 
bands will act satisfactorily as fenders to pre¬ 
vent further mischief. Unions which cannot be 
made tight by screwing up should be taken 
apart and the male connections coated with 


The Automobile Handbook 


163 


soap or red lead, which will render them tight 
for a considerable time. 

After going over the fuel system, the brake 
rods and steering connections should be exam¬ 
ined for loose joints and broken oil and grease 
cups. Grease boots on the drive-shaft joints 
should be seen to be sound, and filled with 
grease. A cleaning out of the dirt from the in¬ 
terior of the mud-pan will often reveal lost cot¬ 
ter pins or nuts, and tend to a more agreeable 
handling of the draineocks, carbureter and fil¬ 
ter. This time will be well spent when the 
chances of fire or accidents arising from faulty 
steering or brake connections are taken into 
account. 

Carbon Deposit—Symptoms of. One of the 

most fruitful sources of trouble in internal com¬ 
bustion motors is that of the carbon deposit. If 
the cylinders get too much oil, or if oil of a 
heavy or inferior grade is used, a portion of it 
will work up past the pistons, where it will be 
evaporated or consumed by the intense heat, 
leaving a deposit of carbon. This may be aug¬ 
mented by too rich a mixture, which serves to 
deposit film upon film of carbon on the inside, 
and top of the compression chamber, and on the 
head of the piston. The films thus formed will 
in time commence to scale, and the projections 
fused by the heat of the explosions will serve to 
prematurely ignite the charge. The symptoms 
are back-firing and knocking in the cylinders 


164 


The Automobile Handbook 


—as li the spark were too far advanced. An 
almost infallible symptom of excessive carbon 
deposit in the cylinders is the motor showing 
plenty of power at high car speeds, but deficient 
in hill-climbing on high gear. At slow engine 
speeds the incandescent carbon projections serve 
to pre-ignite the charge, thereby reducing the 
power of the motor. The cure is to take off the 
cylinder head and scrape off the carbon deposit 
from the top of the piston and inside of the cyl¬ 
inder head. Carbon also will form on the porce¬ 
lain portion of the spark plugs, thereby furnish¬ 
ing a circuit which the high tension current may 
follow, rather than jump the gap between the 
points of the plug. Usually only a part of the 
current will pass by way of the carbon film, 
still leaving a weak spark at the points, which 
in open air, when testing plugs, may seem strong 
enough. This causes intermittent firing. The 
symptoms are similar to a poor contact com¬ 
mutator. This condition is difficult to detect, 
for the reason that when the plug is subjected 
to the usual test of removing from the cylinder 
and closing the electrical circuit, the spark is 
seen to jump free and fat between the sparking 
points. This is because electrical energy which 
is sufficient to jump between two points Vo-inch 
apart in the open air will jump less than 1/16- 
inch in the explosion chamber under 60 pounds 
compression. The causes of overheating in 
motors may be summed up as follows: Poor oil, 
insufficient oil, bad mixture, slow spark, ob- 


The Automobile Handbook 


165 


structed water pipe,'low water and valves out 
of time. 

Carbureter. Almost any carbureter will give 
a reasonably good mixture through a limited 
range of action. Frequently, however, this 
range is found insufficient for a particular en¬ 
gine. If right for low speeds, it is wrong for 
high speeds, and vice versa. 

The theory of carbureter action as regards 
the behavior of the gasoline jet under different 
air velocities is still only partially understood, 
and has been the subject of a great deal of 
more or less blind theorizing, based in many 
cases on wholly inadecpiate data. 

A non-automatic spraying carbureter (i. e., a 
simple nozzle in an air tube) makes no mixture 
at all till the velocity of the air stream reaches 
a certain minimum. Beyond this point, the 
richness increases with the speed. Dilution 
from the auxiliary valve is therefore required 
only when the richness of the mixture exceeds 
the normal. At this point it should be remem¬ 
bered that, so far as the spray is concerned, 
there is no difference between a wide open throt¬ 
tle at slow engine speed (as for instance, up 
hill) and reduced throttle with high engine 
speed. The spraying action is concerned only 
with the velocity of the air past, the nozzle be¬ 
fore the throttle is reached. 

Almost every carbureter is provided with a 
needle valve controlling the spray orifice. With 


166 


The Automobile Handbook 


this provision it is very easy to determine 
whether or not the carbureter is doing as well 
as it should at either low or high speed. For 
example, suppose that we start with an adjust¬ 



ment known to be satisfactory for medium 
speeds. If the low speed performance is under 
suspicion, it is only necessary to increase the 
needle valve opening slightly to ascertain 



































/ 


* 


The Automobile Handbook 167 

whether starting is thereby made easier, and a 
walking pace more smoothly maintained. If 
overheating results, reducing the needle open¬ 
ing will probably cure it. Similarly slight 
changes in the needle opening, without chang¬ 
ing any other adjustment, will determine 
whether or not the mixture is improved by 



less, or more gasoline at high speed. When the 
carbureter is set for a medium speed, if the mix¬ 
ture is weak at low speeds, and rich at high 
speeds, more air should be admitted, but if the 
mixture is rich at low speeds, and weak at 
high, less air should be admitted. Much de¬ 
pends upon the spring. 






























168 


The Automobile Handbook 


It is a characteristic of all springs that their 
flexure is in direct proportion to the load im¬ 
posed, up to the elastic limit of the spring. 
Thus, referring to Fig. 76, if the spring repre¬ 
sented unloaded compresses ^4-inch under a 
load of 2 ounces, it will compress another 14 - 
inch under 2 ounces more, an inch under 8 
ounces total load, and so on. 

Carbureter—Bennett. In this carbureter the 
nozzle is a standpipe P, Fig. 80, with a series of 



openings H at one side, so that with greater 
motor speeds the gasoline rises from this stand¬ 
pipe and escapes from two, three, or perhaps all 
of the openings H, whereas at slow speeds it es¬ 
capes from but one or two. Diagram M, Fig. 
77, shows the gasoline escaping through some of 
the base openings at slow speeds, Ml, Fig. 78, 
shows it escaping from half of the openings at 
half speed, and M2, Fig. 79. shows it escaping 
from all of the openings at full speed, during all 








The Automobile Handbook 


169 


of which time the gasoline level in the float 
chamber remains at the point L, Fig. 77. The 
escape of gasoline throughout the entire height 
of the standpipe P is made possible by having 
the part of the needle valve N, Fig. 77, within 
the standpipe of smaller diameter than the pipe, 
thereby leaving a circular space for the gasoline 
to rise in. The air control of the carbureter is 
through an auxiliary air valve X, Fig. 77, under 
spring tension. The main air supply for the 



low speeds is through opening A, Fig. 80, at 
which time the auxiliary valve is closed. At 
half the motor speed the auxiliary valve is 
partly opened. 

Carbureter Control. There are various meth¬ 
ods of controlling the carbureter from the seat, 
as it is claimed that the best automatic carbu¬ 
reter cannot adapt itself to changes in gasoline 
density, or in humidity, or to the gradual warm¬ 
ing up of'an engine started from “cold.” The 













170 


The Automobile Handbook 


arrangement used on the Holley carbureter is 
shown in Fig. 81. A rod connected by universal 
joint to the needle valve passes through the 
dash and ends in a graduated ratchet-held dial. 
The car is brought up to its proper speed either 
on the road or on a hill, and the handle is 
turned to the right or left until the motor pulls 



the strongest. The float level on the Holley 
carbureter when once set is never changed, ad¬ 
justments being made exclusively by the needle 
valve. In the Ford control, Fig. 82, the needle 
valve is controlled by a rod R, having a forked 
lower end which enters the large adjusting nut 
on the top of the needle valve stem. The upper 































The Automobile Handbook 


111 


end of rod R passes through the dash, and has 
a hand wheel for adjustment purposes. 

Fig. 83 shows the Mora carbureter control, 
in which the main air opening A is controlled 
from the dash of the car by means of lever L. 
This lever works in a semi-circular rack, and is 
connected to ring piece R, which encircles the 
carbureter above the chamber. This ring has 
a series of oblong slots through which the air 



Fig. 81 

Holly Carburetor Control 


enters. By partly rotating the ring, these slots 
can be made to coincide with similar slots in 
the walls of the carbureter, thus regulating the 
air supply. Air auxiliary valve X is controlled 
by a spring. 

Carbureters—Classification of. Carbureters 
may be classified according to the principles of 
their action, as follows: First, the surface car¬ 
bureter, which operates to produce a fuel mix¬ 
ture when air is passed over the surface of a 







172 


The Automobile Handbook 


body of volatile liquid, or when the air circu¬ 
lates around a gauze wicking or metal surface 
saturated with such a liquid; second, the filter¬ 
ing carbureter, in which air is forced under 
suction through a body of liquid from bottom 
to top, so as to absorb particles of its substance; 
third, the float feed carbureter, in which the 
liquid hydrocarbon is sprayed or atomized 



through a minute nozzle and mixed with a pass¬ 
ing column of air. At the present time the float 
feed carbureter using a spraying nozzle appears 
to be the one most generally in use. Carbu¬ 
reters may also be classified according to types, 
of which there are four, as follows: (a) me¬ 
chanical; (b) mechanical, with gasoline puddle 
in the air passage; (c) automatic; (d) auto- 











The Automobile Handbook 


173 


matic, with gasoline puddle in the air passage. 
In type (a) the air and mixture passages are 
opened and closed by some form of mechanism, 
the size of the passages remaining the same un¬ 
til changed by the operator. It is, therefore, 
unable to meet and adapt itself to the varying 
conditions of high speed, slow speed, climbing 



Fig. 84 

Automatic Type of Carburetor 


hills, retarded spark or diminished suction, un¬ 
less the operator promptly regulates the size of 
the passages to suit tin* requirements of the 
motor. Carbureters belonging to type (b) use 
a basin filled with gasoline located in the air 
pipe. This serves to add a certain quantity of 
gasoline at all suctions, and thus helps the car¬ 
bureter when under slow action. 















































































174 


The Automobile Handbook 


But, as the operation of the machine is not 
continuous, and the intervals of time between 
the beginnings of successive strokes vary, ac¬ 
cording to the speed of the engine, the result is 
a variation in the amounts of gasoline supplied 
to the successive charges by the gravity device 
under the different conditions of fast or slow 
speed. Consequently the operation of the de¬ 
vice is not altogether satisfactory. Type (c), 
the usual form of automatic carbureter, see Fig. 
84, takes a portion of its air through a fixed 
opening called the main air opening, and a por¬ 
tion through an opening controlled by a valve 
and a coiled spring called the auxiliary air open¬ 
ing. The main air opening generally represents 
three-quarters of the total air opening. 

A correct mixture having been obtained for 
the minimum suction on which the motor is 
capable of running, is afterwards compensated 
for by the admission of more air, at a rate vary¬ 
ing automatically with the suction. As to type 
(d) a gasoline puddle in the air passage of an 
automatic carbureter has the same objectionable 
features as in a mechanical carbureter. There 
has lately been introduced by several manufac¬ 
turers an automatic carbureter having a me¬ 
chanical adjustment for the gasoline needle 
valve working with the throttle. Aside from 
the fact that the engine starts up easier, this 
arrangement is of no advantage, and increases 
. the complications. As the suction varies 
throughout the intake stroke of the piston, ow- 


The Automobile Handbook 


175 


ing to the varying velocity of the latter in the 
cylinder, the aggregate of any one charge is 
made np of mixtures drawn in under suctions, 
starting from zero, varying in the extreme case 
up to a maximum and returning to zero. 

The Surface Carbureter is at the present 
time almost obsolete, being used only on one or 



two motor-bicycles of European make. The 
rapid evaporation of the vapor in the surface 
carbureter, due to the suction of the motor- 
piston, causes the gasoline after a short time 
to become thick and syrupy, and if some exter¬ 
nal source of heat is not supplied to assist in the 
evaporation it will cease altogether. While the 
surface carbureter is the most economical of 




















































176 


The Automobile Handbook 


the three forms, it is very irregular and erratic 
in its action, and requires constant manipulation 
of the air and gasoline vapor cocks to insure at 
all times an explosive mixture of uniform qual¬ 
ity. 

The Float Feed Carbureter, Fig. 85, con¬ 
sists of two principal parts: a gasoline recepta- 



Fig. S6 

Multiple Spray Carburetor 


cle which contains a hollow metal or a cork 
float, suitably arranged to control the supply of 
gasoline from the tank or reservoir, and a tube 
or pipe in which is located a jet or nozzle in 
communication with the gasoline receptacle. 
This tube or pipe is called the mixing chamber. 
The gasoline level is maintained about one-six¬ 
teenth of an inch below the opening in the jet 
























































The Automobile Handbook 


177 


in the mixing chamber. The inductive action 
of the motor-piston creates a partial vacuum in 
the pipe leading from the mixing chamber of 
the carbureter to the motor, thereby causing 
the gasoline to flow from the jet and mixing 
with the air supply, to be drawn into the cylin¬ 
der of the motor in the form of an explosive 
mixture. 

Spraying Carbureters. In this type of car¬ 
bureter the quantity of gasoline delivered is 
not proportional to the volume of air delivery 
at different rates of flow. This difficulty has, 
however, been met by providing a supplemen¬ 
tary air inlet to the carbureter, which may be 
regulated by the driver at will. 

Another method of correcting the variations 
in the proportions of the gasoline charge is 
shown in Fig. 86, and consists in providing a 
second spray nozzle. In the majority of cases 
in which multiple nozzle carbureters are used, 
there are two nozzles, practically two carbure¬ 
ters, a small one for idle running, and slow 
speeds, and a larger one for heavy work. In 
some instances, three, and evmi four nozzles are 
used. 

The Venturi Tube Carbureter operates on 
the principle that if two converging air nozzles 
have their small ends brought together, there 
is a point where the suction remains practically 
constant, therefore if the fuel nozzle be located 
at this point the result will be, a constant mix¬ 
ture at all speeds. In a carbureter of this type 


178 The Automobile Handbook 

there are no auxiliary spring controlled air 
valves, no moving strangling cage, nor any me¬ 
chanical interregulation between the air, and 
the gasoline. 

An elementary Venturi tube is shown in Fig. 
87, which represents the tube A having a head 
of water on it. The discharge at A is greatly 
increased by the addition of the divergent noz¬ 
zle at the outlet end. Under these conditions, 




Principles of the Venturi Carburetor 

the velocity of flow in the throat at A is greater 
than that produced by the head H. When a 
pressure gauge is placed at A the pressure is 
found to be less than atmospheric; in fact, the 
fluid is discharging into a partial vacuum, and 
the velocity at A is due to the head H plus the 
head due to the vacuum. Advantage is taken 
of this fact by placing the gasoline outlet at 
the point A, in which case the velocity of the 


l 


































The Automobile Handbook 


179 


suction controls the flow of gasoline at all times 
thus giving a perfect mixture. 

Carbureters—Inspection of. The float valve 
of the carbureter should be tested for leaks by 
opening the valve between it and the tank and 
looking for gasoline drip. If gasoline escapes, 
it may simply be because the float is set too 
high, so that it does not close the needle valve 
before gasoline issues from the spray nozzle. 
Or, it may be that the valve itself, leaks. 

At this stage, it is well to assume that the 
float is properly adjusted, and to begin by shut¬ 
ting off the main gasoline valve, and then un¬ 
screwing the washout plug below the needle 
valve. It may be found that dirt, waste, or a 
splinter of wood has got past the strainer, 
through which, presumably, the gasoline passes 
on its way to the float, and is lodged in the 
needle-valve opening. It may be of advantage 
to open the top of the float chamber, which can 
usually be done without disturbing other parts, 
and take out the float and needle valve. A lit¬ 
tle gasoline washed down through the needle- 
valve orifice will then generally carry away any 
dirt that may have clung to the valve when the 
plug was unscrewed. If the gasoline still drips 
when the parts are reassembled, the mixing 
chamber should be opened and the top of the 
spray nozzle examined to see if gasoline is es¬ 
caping from it. An electric light should be - 
used in making an examination of the carbu¬ 
reter, as, with any other illuminant, a fire might 


180 


The Automobile Handbook 


be started. The portable electric flashlights 
sold everywhere at a moderate price answer the 
purpose very well. 

Occasionally a carbureter is found to be too 
large for the engine, or to have too large a 
spray orifice. The advice has been given in 
such a case, to reduce the size of the spray ori¬ 
fice by lightly pening the top of it with a ham¬ 
mer. This is counsel of doubtful value, even 
if the hole be.afterward reamed true, since it is 
manifest that the burr formed in the top of the 
orifice cannot possibly be deep enough to be at 
all regular in its form. It will almost inevita¬ 
bly throw a jet slantwise, instead of straight, 
and this jet failing to strike the main part of 
the air stream will be only partly atomized, 
with resulting misfiring and general bad be¬ 
havior, especially at low speeds. If a new noz¬ 
zle of smaller size cannot be substituted, the 
best thing to do in case there is no needle valve 
to adjust the flow of gasoline to the jet is prob¬ 
ably, to warm the ingoing air as much as possi¬ 
ble, in order to make evaporation by tempera¬ 
ture take the place of atomizing due to the air’s 

velocitv. 

•/ 

Carbureter—Scott-Robinson Type. Fig. 88 

shows a vertical section of the Scott-Robinson 
Carbureter. In designing this carbureter M. 
Scott-Robinson, the inventor, has kept in mind 
the possible power to be developed by the mo¬ 
tor rather than the crankshaft speed; his rea¬ 
soning being that at times the motor pulls 30 


The Automobile Handbook 


. 181 


horsepower at 1000 revolutions per minute, 10 
horsepower at 100 revolutions per minute, 15 
horsepower at 750 revolutions per minute and 
15 horsepower at 500 revolutions per minute, 
from which he deduces that the mixture neces¬ 
sary for the running of this engine must vary 
according to the horsepower needed, and conse¬ 
quently be independent of the crankshaft 
speed. It is customary in automatic carburet¬ 
ers to have the mixture governed almost solely 
by the crankshaft speed, irrespective of the 
power the motor is generating at the time. In 
order to achieve mixture in proportion to horse¬ 
power the Scott-Robinson carbureter is so de¬ 
signed that it has one jet for every 2 horse¬ 
power, so that with the engine working with a 
20 horsepower load fifteen gasoline jets are in 
operation. 

Referring to Fig. 88, A is the normal air 
opening, B the exit to the induction pipe, and 
C the needle valve governing the flow of gaso¬ 
line to the float chamber carrying the float F. 
Within the carbureter proper is a standpipe 
F, in the top of which is a series of thirty ori¬ 
fices, H through which gasoline can escape. 
These orifices are in the center of an air regu¬ 
lating float, K which can move piston-like in 
the casing L. This air-regulating float carries 
a piston M which fits in the top of the standpipe 
E, its duty being to uncover and cover the ori¬ 
fices H according as the air regulating float K 


182 


The Automobile Handbook 


rises or falls. In the bottom of float K is a cir¬ 
cle of circumferential openings N. 

In following the course of the air and gaso¬ 
line, as well as studying the operation of this 
^carbureter, it should he remembered that the 



Fig. 88 

Scott-Robinson Carburetor 


air entering is at first completely confined in 
the chamber V until the air-regulating float K 
is raised, permitting the air to pass around this 
float and follow the direction indicated by ar¬ 
rows A1 and A2. This air, in its course, passes 





























































The Automobile Handbook 


183 


the openings N in valve K and the suction of 
the motor is such as to tend to draw the air out 
of the interior of K. The gasoline can at such 
times flow out of the orifices H. This gasoline 
escapes through the openings N, mixes with 
the air and passes through to the motor. With 
the throttle X at its half-load position the 
amount of mixture required would be 1950 cu¬ 
bic feet per hour, at which consumption the 
float K rises to its half-lift position, bringing 
half of the orifices H into work. Because the 
weight of the float Iv is constant, the velocity 
of the air past, the holes N is constant, and the 
vacuum within float K is also constant, thereby 
insuring a constant pull on the gasoline in the 
standpipe E, which it is claimed eliminates the 
varying momentum of the escaping gasoline, 
which is claimed to be so common in carburet¬ 
ers where the pull on it is in proportion to the 
crankshaft speed. Because the air mixture must 
always flow past the air-regulating float K, ac¬ 
cording to the arrows A1 at a constant velocity 
and the head of the liquid in the standpipe E 
remains constant, the inventor claims that the 
delivery of the fuel must be varied in volume 
only, which he accomplishes in the following 
manner: Supposing the weight of float K be 
such that the mixture velocity in the direction 
of the arrows A1 is 100 feet per second. At a 
half-load position the area past the base of the 
air regulating valve K would be .875 square 
inch, which would be sufficient for 1950 cubic 


184 


The Automobile Handbook 


feet of mixture per hour; or enough to develop 
15 horsepower, or half load. Assuming the use 
of 2 per cent mixture of gasoline, the amount 
of gasoline vapor contained in the 1950 cubic 
feet of mixture would make it necessary for the 
jets to deliver gasoline at the rate of 1.35 gal¬ 
lons per hour. 

Should the throttle be moved to its full load 
position, or 30 horsepower, the air regulating 
float K immediately rises to its maximum posi¬ 
tion bringing all of the orifices or jets H into 
operation. At this position 3900 cubic feet of 
mixture per hour is needed, calling for a pas¬ 
sage area past the base of float K of 1.56 square 
inches, and a full consumption of 2.7 gallons 
per hour. Considering the use of a full-pow¬ 
ered car, with few opportunities of using the 
maximum power and, further assuming that the 
lower orifices II emit up to half the maximum 
power, they could be adjusted so as to deliver 
a rather weak mixture suitable for around 
town work. Also, all jets could be propor¬ 
tioned to give the maximum power at higher 
loads, which w r ould be suitable for touring pur¬ 
poses. As to the possibilities of clean exhaust 
under different conditions of this carbureter an 
analysis showed 1.5 per cent of CO, the analy¬ 
sis being made from a dozen samples. Further 
evidence as to the operation of this carbureter 
exists in the fact that an 18-22-horsepower car, 
weighing 2576 pounds, on a long trip averaged 
28 miles to the gallon. 


The Automobile Handbook 


185 



Chain Drive—Double. Fig. 89 shows a plan 
view of a double chain drive chassis. The rear, 
or driving axle, is made solid and stationary. 




















































































































































186 


The Automobile Handbook 


A large sprocket wheel is bolted to the inside of 
the spokes of each driving wheel, and a cross, 
or countershaft is carried by the chassis at a 
point a short distance ahead of the driving axle. 
The countershaft is divided at or near its 
central portion, and its two inner ends are con¬ 
nected to the appropriate parts of the differen¬ 
tial gear, while the outer ends carry the two 
small sprockets over which the chains travel. 
The countershaft usually passes through the 
speed change gear case. Lubrication of the 
driving axle bearings is accomplished by pack¬ 
ing with grease, or by means of grease cups, or 
oil holes, the bearings of the counter shaft are 
also generally lubricated by the use of grease 
cups. The advantages of the double chain 
drive, are that being fixed or stationary, it may 
be given a form most suitable for carrying 
heavy and variable loads. In this form of trans¬ 
mission the differential gear is relieved from 
carrying any weight, except its own, and may 
be arranged to run in oil. The only disadvant¬ 
ages worth mentioning are, that two chains in¬ 
stead of one are required, and that noise of the 
car is somewhat increased. 

Chain Drive—Single. The simplest form of 
chain drive is the single chain, used on light 
cars and runabouts. In this type the small 
sprocket is attached to the engine shaft, and 
the large sprocket is connected to the rear axle, 
while the change speed gears are located on the 


The Automobile Handbook 


187 


engine axle, and the differential on the rear 
axle. 

The chain may be either inside or outside the 
chassis. On cars using the single chain, the 
driving axle is of the live type, being divided 
into two parts, to the outer end of which is se- 
t-urely fastened, one of the drivers. At the point 
of division of the axle, which is usually at its 
center, the differential gear is placed, to which 
are connected the inside ends of the halves of 
the axle. 

A steel tube usually encases each half of the 
axle, and the inner ends of these tubes are 
brazed to the metal case enclosing the differ¬ 
ential. This tube is firmly bolted to the lower 
portion of the rear springs. It also serves to 
carry the axle bearings. An underrunning 
brace is applied to the axle tube on cars de¬ 
signed to carry heavy loads. The disadvantages 
attending the use of the single chain are, first, 
that the shaft which carries the load must be 
divided at its center, and second, there is a con¬ 
stant strain on the rear axle, due to its turning 
moment. In order to prevent the rear axle of 
chain driven cars from being drawn toward the 
engine axle, or countershaft when power is ap¬ 
plied to the chain, distance rods or tubes are 
used, which are adjustable as shown by Fig. 90. 

The owner or driver of a chain-driven car 
should learn very early in his driving career to 
care for the driving chains in a proper manner. 
While chains have been known to run an entire 


188 


The Automobile Handbook 


season without any care or additional lubrica¬ 
tion, this practice is deprecated. To care for a 
chain properly, one should get into the habit of 
lubricating it often, and so time these intervals 
that they occur before the chain is in need of 
the oil. In addition to this regular lubrication, 
there should be some set time at the end of 
which the automobilist takes the chain off, 
cleans it thoroughly, and inspects it to detect 
faults. 



Fig. DO 

Method of Tightening and Loosening Chain 


A month is a good length of time for this, 
and an excellent way to proceed is to take the 
chain off and throw it into a pan of kerosene. 
In the morning, all of the dirt will have passed 
from the chain to the liquid, and can be found 
in the bottom of the pan. Take the chain out 
and throw the liquid and dirt away. Then clean 
the pan, and in it wash off all traces of the ker¬ 
osene with gasoline. Having done this, hang 
the chain up to let the gasoline evaporate. 


















The Automobile Handbook 


189 


The chain then will be both clean ancl dry. 
Now inspect all rollers, links, rivets and bush¬ 
ings, taking note of any unusual wear as indi¬ 
cated by looseness or play. If defects are 
found, they should be remedied. Then, having 
the chain clean, dry, inspected and passed upon 
as O K, an excellent method is to soak it, or, 
better, boil it in a heavy melted lubricant. The 
best quality of beef tallow mixed with a little 
graphite is good. Many do not like the latter, 
in which case a high-grade oil may be substi¬ 
tuted for the purpose. 

Change Speed Gears. When a gasoline en¬ 
gine is loaded above a certain limit it slows 
down, and the intervals of time between ex¬ 
plosions in each cylinder become so far apart 
that the engine begins to labor, and will finally 
stop altogether, unless some means is provided 
whereby the revolutions of the engine may be 
increased without increasing the number of 
revolutions of the driven shaft, or car axle. 
This is accomplished by means of the change 
speed gear, of which there are two classes, viz., 
those in which an infinite series of variations 
in speed ratio is possible, and those in which 
only a comparatively small number of step-by- 
step ratios can be utilized. In the first class 
are several styles of belt and friction disc 
drives, while in the second class are the change 
speed gears proper, namely, sliding gears, indi¬ 
vidual clutch gears, and planetary gears. 

Belt and friction drives constitute the only 


190 


The Automobile Handbook 


practical forms of change speed devices in 
which variation from the highest to the lowest 
speed may be possible. In other change speed 
gears the ratio is changed by passing from one 
to another in a series of definite steps. 



t- 

ci 

<v 

o 

<D 

a, 

OQ 

_ tuo 

05 c 

. c$ 

5° 

O 
efi 


id 

o 

• H 

o 


Friction Drive. One of the most simple 
methods of changing the speed ratio between 
the motor and the driven shaft is the friction 
drive, which in its simplest form consists of 
two discs at right angles to each other, see Fig. 



























































The Automobile Handbook 


191 


91, in which b is the fly wheel, the exterior sur¬ 
face of which is made a true plane, and usually 
covered with a special friction metal. A hori- 
zontal shaft located crosswise of the car body 
carries a friction pulley c, in close proximity to 
the surface of the fly wheel b. 

Friction pulley c while secured from turning 
on shaft, may at the same time be shifted along 
at the will of the operator, and thus be 
brought in contact with any portion of the sur¬ 
face of the flywheel, from its center to its outer 
edge. The shaft also carries on its outer ends, 
the sprocket wheels w T hich drive chains e and 
f, by means of which the power is transmitted 
to the drivers. In this device if the friction pul¬ 
ley c be brought in contact with the exact cen¬ 
ter of fly wheel b, no motion will be imparted 
to c, but if it be moved outward from the 
center of the flywheel it will revolve, the num¬ 
ber of revolutions it makes being governed by 
its distance from the center. The maximum 
speed is attained by friction pulley c when it is • 
brought into contact with the surface of the fly 
wheel near the periphery of the latter. All po¬ 
sitions of friction pulley c upon one side of the 
center of fly wheel b impart a forward motion 
to the car, and all those on the other side of the 
center impart a reverse, or backing motion. The 
traversing movement of pulley c along its shaft 
is usually produced by a hand lever provided 
with a notched quadrant, whereby the pulley is 
held at all times in some one of the many posi- 


192 


The Automobile Handbook 


tions giving graduations of speed. The method 
usually employed for making and breaking con¬ 
tact between the friction pulley, and flywheel 
face, consists in mounting the bearings of the 
cross, or countershaft in swinging brackets. An¬ 
other method is to mount these bearings in ec¬ 
centric housings, a slight rotation of which in 
the bearing brackets will cause the shaft and 
with it the pulley to approach, or recede from 
the face of flywheel b. The movement of the 
shaft toward, or away from the flywheel is pro¬ 
duced by a ratchet retained pedal through a 
reducing linkage, which multiplies the foot 
pressure. 

Double Disk Friction Drive. The limitation 
of the single disc and wheel to small power, and 
light loads, has led to the development of the 
double disc, double wheel type of friction gear 
illustrated in Fig. 92. 

The engine shaft is extended, and carries two 
disc fly wheels A and B, while friction pulleys 
C and D are each carried upon one half of 
the cross shaft which is divided at its center. 
Friction pulleys C and D are made to slide 
along the shafts H and F, and are controlled 
by a common sliding mechanism, so that they 
always bear upon points of discs A and B, hav¬ 
ing the same velocities. Driving contact is ef¬ 
fected by swinging, shafts H and F in a hori¬ 
zontal plane, and it is obvious that if one of the 
pulleys, D for instance, is pressed against the 
face of A, it will revolve in one direction, while 


The Automobile Handbook 


193 


if brought to bear on B it will revolve in the 
opposite direction, thus providing for a go- 
ahead, or a back-up motion being imparted to 
either friction wheel at will, dependent upon 
whether it is in contact with the forward, or the 



rearward disc. It is also evident that if one 
of the wheels, say D, is pressed against A, and 
the other wheel C is also pressed against B. 
their shafts will rotate in opposite directions 
The ratio of the common angular velocity of the 


























































194 


The Automobile Handbook 


wheels and their shafts to that of the discs is 
in proportion to their distance from the center 
of the discs. Sprockets upon the extremities of 
shaft H and F drive the road wheels by chains, 
and sometimes no differential is employed, 
power being shut off when turning comers, or, 
if not, the inevitable slip is divided between the 
frictional contacts, and the contacts of the tires 
with the road. A differential may be mounted 
in either shaft H or F at will. 

Instead of the two shafts H and F being sep¬ 
arate, they may be joined to form a continuous 
shaft and pivoted in the center. The shaft as 
a whole is capable of being slightly swung in a 
horizontal plane about its center, so as to bring 
friction wheel D in contact with one disc, and 
friction wheel C in contact with the other, thus 
producing either the forward or reverse drive. 
In this case a single sprocket is carried by the 

shaft and drives a live rear axle. 

_ • 

Bevel Friction Drive. The main objection 
to the types of friction drive hitherto described 
is, that they are all subject to more or less slip¬ 
page. This defect is eliminated by the use of 
the bevel friction drive shown in Fig. 93. The 
reason for this is that, when two cones are in 
frictional contact, their common points of con¬ 
tact will have equal velocities. Referring to 
Fig. 93, the engine shaft E carries at its rear 
end a disc flywheel having a bevel rim A, and 
a plane disc face B. Cross shaft F carries the 
friction pulley provided with the bevel face D, 


The Automobile Handbook 


195 



Fig. 93 

Chassis of a Two-Cylinder Car Using the Bevel Frietion Drive 

































































































































































aapanp 


196 


The Automobile Handbook 


also the flat cylindrical face C. At low speeds, 
and on the reverse, this apparatus acts as a sin¬ 
gle disc and wheel drive, the disc face B being 
moved backward to bring it into contact with 
face C of the friction pulley, which is made to 
traverse the shaft to any desired position. To 
secure maximum speed, the friction member is 
moved along on the shaft until its bevel face D 
is in alignment with the bevel face A of the 
flywheel which is then moved backward on 



shaft E until the two beveled surfaces are in 
close contact. The drive is then practically by 
a set of bevel gears having an infinite number 
of teeth, as the two surfaces A and D have a 
purely rolling action upon each other. 

Fig. 94 shows another form of bevel friction 
drive, in which there are no graduations of 
speed, except as the speed of the engine varies. 
The action is as follows: When A is in contact 
with C and D, it drives at forward speed, 
sprocket F direct, and sprocket K through 





































































The Automobile Handbook 


197 


gears G and H. To produce the reverse 
speed, B is brought in contact with C and D. 
The friction discs C and D are of gray iron, 
while the faces of A and B consist of tarred 
fibre. A stepped friction change speed gear is 
shown in Fig. 95 in which F is the crankshaft 
extension carrying bewd pulleys C and E of 
exactly equal dimensions, and also bevel pulley 
D of smaller diameter, all three pulleys being 
slidable on the shaft. A and B are beveled fric¬ 
tion discs mounted on the cross shafts H and 
G, the end of G carrying the driving sprocket 
K. Shaft H carries one of the pair of spur- 
gears L, while the other member is on a short 
shaft which carries sprocket J. 

Upon the adjacent faces of discs A and B are 
formed another pair of bevel pulleys of consid¬ 
erably smaller diameter than the two outer 
bevel faces, thus permitting of a step upward 
in speed if desired. 

The action is as follows: When E is moved 
slightly forward on shaft F, it is brought into 
contact with the large diameter bevel faces of 
A and B, driving them in opposite directions. 
But the direction of rotation of sprocket J is 
corrected by the pair of gear wheels L, the re¬ 
sult being a uniform direction of rotation for 
sprockets K and J. 

If pulley D be placed in contact with the in¬ 
side bevel faces of A and B, the result will be 
a higher speed, owing to the fact that the diam- 


198 


Th-e Automobile Handbook 


eter of D is nearly as large as the diameters of 
the inside steps of A and B. 

A reverse motion is obtained by bringing pul¬ 
ley C into contact with the large diameter faces 
of A and B. 



Pulley Change Speed Gear. A pair of pa¬ 
per faced pulleys, A and B, ■ Fig. 96, are 
mounted on each end of the crankshaft. The 
smaller pulleys of each pair are slidable by 
means of splines, and are controlled by a foot 




































































The Automobile Handbook 


199 


pedal, which when operated causes them to tel¬ 
escope the larger pulleys. To the front, and be¬ 
low the engine is a countershaft, S, on which 
are mounted two sets of aluminum friction pul¬ 
leys, C and D. Each half of the countershaft 
is independently controllable. The driving 
sprockets are carried on the ends of this coun¬ 
tershaft. A side lever controls the position of 
countershaft pulleys with reference to the pul¬ 
leys on the engine crankshaft. By manipulat¬ 
ing the slide lever and the foot pedal the two 
forward speeds are obtained. The reverse is 
through a pair of idlers controlled by a second 
foot pedal, which shifts them into engagement 
with the low speed pulleys. On account of 
there being a double set of pulleys and the 
method of control, no differential gear is used. 

Friction Drives—Materials For. In fric¬ 
tion drives, one of the surfaces in contact is 
generally a metal, while the other surface is 
composed of some kind of organic material, of 
a slightly yielding or conforming nature. Cast 
iron with cork inserts may be used for the me¬ 
tallic surface, the cork inserts serving to in¬ 
crease the co-efficient of friction, besides absorb¬ 
ing any oil that may accidently reach the sur¬ 
faces. Aluminum is no doubt the best material 
for the metallic surface, on account of its plastic 
nature. Copper also possesses similar proper¬ 
ties. For the non-metallic surface, leather is 
good so long as oil is kept from accumulating 


200 


The Automobile Handbook 


on it, but its co-efficient drops rapidly as soon 
ns oil gets between the contact surfaces. 

Some kind of vegetable fibre, made into a 
paper or mill board, seems to be the preferred 
material, and it is comomn to treat such paper 
with a tarry composition, which tends to raise 
the co-efficient of friction, as well as to render 
its value more nearly constant under the influ¬ 
ence of water and oil. 

The non-metallic friction face is the one worn 
out in service, or at least it wears the more rap¬ 
idly. This part of the combination, though of 
limited life, can be renewed at a comparatively 
small expense, and it fails only after giving due 
notice. It is the practice to make the disc face 
metallic, and the friction wheel rim non-metal¬ 
lic. Great care should be exercised in starting 
the car, as at such times the disc is liable to 
slip at speed upon the rim of the friction wheel 
which is then either stationary or revolving 
very slowly, and flat spots may very easily be 
worn upon its surface. 

The Planetary Change Speed Gear. This 
system of transmitting the power at various 
speeds comprises a high-speed connection for 
the direct drive, and an arrangement of gears 
that reduces or reverses the motion when one 
or another drum on which these gears or pin¬ 
ions are mounted is held stationary. Most 
planetary systems give only two forward speeds 
and the reverse, but in some instances they are 
made to give three forward speeds. They are 


The Automobile Handbook 


201 


used chiefly on small automobiles, or runabouts; 
but when cheapness of construction is an object 
they are sometimes employed on touring cars. 

In Fig. 97, is shown one form of planetary 
system. The gear a is the only one keyed to 



the engine shaft b. The gears c, d and e all 
mesh with the gear a, and are made long enough 
to extend beyond a and mesh with the gears 
f, g and h in pairs. The last three gears in 
turn extend beyond the gears c, d and e, and 































202 


The Automobile Handbook 


mesh with the gear i, which is keyed to a sleeve 
connected to the drum j. The gears c, d, e, f, 
g and h turn on pins fastened to the drum k, 
but only the gears c, d and e mesh with a, and 
only f, g and h mesh with the gear i which 
turns loosely on the shaft b. The internal gear 
1 meshes only with the gears c, d and e, and 
is rigidly connected to the sprocket m that 
drives the automobile. The cover n is attached 
to the face of the drum k by means of screws, 
thus forming an oil reservoir that keeps the 
gears well lubricated when the automobile is 
running. There are separate brake bands 
around the drums j and k, and a friction disc 
keyed to the shaft just outside of the drum j. 

When the friction disc is pressed against the 
drum j, the gear is held so that it must turn 
with the shaft; consequently, the entire me¬ 
chanism is locked together and the sprocket m 
turns at its highest forward speed. If now the 
friction disc is released and the brake band 
around the drum j is applied so as to hold it 
from turning, then the gear a turns the gears 
c, d and e, causing them to turn the gears f, 
g and h; but, as the gear i is held stationary 
with the drum j, the gears f, g and li, and also 
the drum k, to which they are attached, must 
revolve around the gear i in the same direction 
as the shaft turns, but more slowly. The gears 
c, d and e turn on pins that are fastened to the 
drum k; consequently, they revolve with it as 
they turn on their axes and thus cause the in- 



The Automobile Handbook 203 

ternal gear 1 and the sprocket m to turn in the 
same direction as the shaft. This gives the slow 
forward speed. 


When the drum j is released, and the drum k 
is held by a brake band, the gears c, d and e 
are caused to turn on their pins, and conse¬ 
quently drive the internal gear 1 in a direction 





204 


The Automobile Handbook 



Fig. 97b 

Combination Transmission and Differential Gear 


opposite to that of the engine shaft, driving the 
automobile backwards. When the brake bands 
and friction disc are all free from the drums, 
the gears turn idly, and if the engine is running, 
no motion is transmitted to the sprocket and 
the automobile stands still. 

Chassis. The word chassis since its adoption 
into the English language, is taken to mean the 
frame, springs, wheels, transmission and in fact 







The Automobile Handbook 


205 


all mechanism except the automobile body. In 
its original French it does not mean all this, but 
is strictly restricted to mean the frame, or the 
frame and springs. 

Chauffeur. This term when literally trans¬ 
lated means the stoker or fireman of a boiler. 
The use of the word has been extended to the 
operator of a motor car, but does not usually re¬ 
fer to the paid driver, who is generally known 
as the mechanician or mechanic. 

Circuit-breaker. A circuit breaker is a de¬ 
vice consisting of either a solenoid, or an elec¬ 
tromagnet which acts automatically to break 
the circuit of a storage battery charging plant, 
when a condition of either too low, or too high 
voltage exists. 

Circulating Pump. The circulating pump is 
used in the belief that it affords a means for 
regulating the temperature of the jacket water 
supply, which would not always be the case 
with a thermal-syphon system. Such is not the 
case, as the pump, being driven direct from the 
motor, operates at a speed which varies with 
the motor speed. On starting the motor, it 
pumps cold water into the jacket. It pumps 
slowly at slow speeds, although the motor may 
be taking a full charge and heating rapidly. It 
pumps fast at high speeds, although the wind 
pressure and its consequent cooling effect may 
be very great. If a circulating pump could be 
used in connection with a device to control the 

i 


206 


The Automobile Handbook 


regulation of the motor temperature, the results 
would be more satisfactory. 

Rotary pumps used in the water circulating 
system of gasoline automobile motors are of two 
forms, centrifugal and positive, or force-feed. 
A positive or force-feed rotary pump is shown 
in Figure 98. An annular ring around the 
pump shaft carries two blades, one of which is 
hinged to, and the other attached directly to 



PUMP 


Fig. 9S 

the pump shaft. The outer ends of the blades 
are supported in the periphery of the annular 
ring, and rotate eccentrically with it. The 
pump shaft is concentric Avitli the pump cham¬ 
ber, but the annular ring is located eccentrically 
around the shaft, which drives it by means of 
the fixed blade on the shaft. 

Figure 99 illustrates another form of posi¬ 
tive-feed rotary pump, in which the pump shaft 
is eccentrically located in the pump chamber. 



The Automobile Handbook 


207 


A short cylinder which forms a part or portion 
of the pump shaft, carries two blades in a slot¬ 
ted opening parallel to, and coincident with the 
axis of the pump shaft. These blades are kept 
in contact with the interior periphery of the 
pump chamber by means of coil springs, located 
between the blades as shown. Rotation of the 
cylinder in the pump chamber causes a sliding 
or reciprocating action of the blades, due to 



PUMP 


Fig. 99 

the pressure of the coil springs between their 
inner ends. 

Cleaning Car Body. In using soap for clean¬ 
ing, the method adopted should be one that will 
preclude the possibility of getting raw soap on 
the paint and varnish, and also to prevent waste 
of soap. The soap should be thoroughly dis¬ 
solved in water before using. In order to do 
this proceed as follows: Dissolve one pound of 
high grade soft oil soap to each gallon of water, 










208 


The Automobile Handbook 


and use from a half to a full pint of this solu¬ 
tion to each pail of wash water, just enough 
in fact to form a good suds. Another for¬ 
mula is: dissolve from 5 to 6 lbs. in a 50 gallon 
barrel, and fill the barrel full of water; then dip 
this solution out in a pail for washing. Do not 
put raw soap into the pail which is used for 
washing the car. Wet the car first with clean 
water, then wash with the suds, and immedi¬ 
ately rinse with hose or sponge and clean wa¬ 
ter. After the car is dry, rub with soft cloth 
or chamois to bring up a high polish. 

Clutch. Clutches may be classified as fol- 
lows: a, cone; b, disc; c, band; cone clutches 
may, in turn, be subdivided as follows: a, metal 
to metal; b, leather faced; c, cork insert; while 
disc type may be classed as: a, leather faced; 
b, multiple disc; c, cork insert; and band 
clutches may be put down as of the a. constrict¬ 
ing, b, spiral, or c, expanding types. Clutches, 
of whatever type or class, have but one prime 
object, i.e., to enable the operator to start and 
stop the ear without having to stop the motor. 
There is a secondary consideration, if we take 
into account the fact that it is convenient to be 
able to slip the clutch, on occasion. Some types 
lend themselves to this secondary purpose with 
greater facility than others, and it is also true 
that some clutches are most easy of application, 
all things considered. 

As clutches are at present designed, the ques¬ 
tion is, can slipping be tolerated? or, can 


The Automobile Handbook 


209 


dutches be slipped to control the speed of a 
car? It is believed not. The average clutch 
has very little of the character of the average 
braking system, and when it comes to brakes 
they do not last so long that it is desirable to 
wear them ont sooner than they will naturally 
need replacement. In other words, it seems 
quite out of the question to consider the 
clutches of today as suitable for the double pur¬ 
pose of clutching and speed controlling, by way 
of slipping the clutch at will. It is not uncom¬ 
mon to hear autoists talking of the multiple 
disc clutch as one that undergoes little or no 
deterioration as a result of continuous slipping 
under variations of load. 

They seem to think that the large surface ex¬ 
posed, especially in view of the fact that the 
discs are submerged in oil, will prevent damage 
if the clutch is caused to slip. They forget that 
the discs are thin, and also that they are loose 
on the splines, keys, or feathers that prevent 
the discs from rotating. No member keyed onto 
a shaft will stand much abuse. This is espe¬ 
cially so, if the member has but little bearing 
surface on the key. Even a considerable num¬ 
ber of such members working in unison will 
fail to stand up under the work because the 
joint is not firm. Lost motion is bound to re¬ 
sult in more lost motion in a short while, and 
in a multiple disc clutch the discs soon fray oin 
and interfere with each other, and with the 
clutching functions, within a space of time so 


210 


The Automobile Handbook 


short as to surprise even those most experi¬ 
enced in the use of this type. 

Band Clutch. A band, or friction ring, 
clutch, is shown in Fig. 100. The wheel which 
is connected to one of the shafts is shown at a, 
and the band, or ring which is connected to the 
other shaft and which is made in two parts, is 
shown at b and c. At d and e are curved arms 



pivoted at f and g. The links li and i connect 
these curved arms to the parts b and c of the 
band. By means of a fork, and tapered sleeve, 
not shown, the ends j and k of the arms are 
forced apart when the clutch is brought into 
use. This throws toward the shaft the ends 1 
and m of the levers d and e, and brings the two 
parts b and c of the clutch ring in contact with 













The Automobile Handbook 


211 


the friction or driving surface of the wheel a, 
which is thereby forced to turn with the driving 
shaft. The band clutch has had many expo¬ 
nents in the motor car art, but is open to cen¬ 
trifugal effects to such an extent that it re¬ 
quires considerable ingenuity to overcome trou¬ 
bles arising therefrom. At high engine speeds 
the operating levers have been so arranged as 
to lower the normal expanding pressure. 



Cone Clutch. There are a number of modi¬ 
fications of this type of clutch, the general prin¬ 
ciples of which are illustrated in Fig. 101. The 
flywheel a is secured to the shaft b by means 
of bolts through the web of the wheel. At c is 
an expansion ring into which the friction cone 
d fits. The helical spring e holds the cone 
against the expansion ring with the required 










































212 


The Automobile Handbook 


amount of force. At f is a ball bearing that 
takes the end thrust when the cone is pulled 
away from the expansion ring. 

The arms g are coupled to the shaft that turns 
with the friction cone. Ordinarily the two parts 
of the clutch are held together by the pressure 
of the spring, and when it is desired to discon¬ 
nect the cone, a foot pedal is forced down so 
as to act on a fork and sleeve and pull the cone 



away from the expansion ring. When the pedal 
is released, spring e forces the clutch into action 
again. 

Fig. 102 is a sectional view of a form of 
leather faced cone clutch in which the male part 
of the cone moves axially toward the engine. 
Fig. 103 shows a clutch constructed on the 
same principle, but in place of having one 
strong actuating spring surrounding the axis, 
it has three weaker spiral springs near the pe- 



























The Automobile Handbook 


213 


riphery of the male member. Fig. 104 is a verti¬ 
cal section of a clutch suitable for a 50 H. P. 
car. The cone angle is 13 degrees, and the di¬ 
ameter 16 inches, with a total frictional area of 
128 square inches, the axial pressure resulting 
from the spring being 375 lbs. A small spiral 
plunger spring A under the leather face B 
causes it to pick up the load more quietly and 
smoothly. Fig. 105 illustrates an early form 
of clutch intended for a car of about 20 H. P. 
One form of toggle joint is also shown at A. 



Fig. 103 


This clutch also has multi-springs for creating 
the proper frictional contact, and a peculiar 
form of spring application simple in the ex¬ 
treme. A multi-cone clutch is shown in section 
in Fig. 106. Its action is as follows: When the 
clutch engages, the smallest cone seizes first, 
commences to revolve and subjects the spiral 
springs between the next two clutches to tor¬ 
sional movement, which draws them together 
and brings the two outer cones into action; the 

idea being that the small clutch shall slip, tend 

, \ 













214 


The Automobile Handbook 


to accelerate the car, that the medium clutch 
shall behave in a similar manner and that when 
the large clutch comes into play the three com¬ 
bined pick up the load and move the car. 

The so-called inverted cone is well illustrated 



in figure 107. The reversed cone is contained 
in an extension A, built onto the flywheel B. 
When the cone is disengaged it moves toward 
the engine, exactly reversing the action of the 
foregoing type. This clutch has its adherents, 
















































































The Automobile Handbook 


215 


and it is a good one, differing very slightly, if 
properly assembled, in its efficiency from the 
direct-acting cone. It may be kept free from 
dirt and oil much more perfectly than in tin* 
other form. 

Disk Clutch. A clutch of the multiple-disc 
type is shown in Fig. 108. A two-arm spider 
a, keyed to the shaft b, serves to hold in place a 
number of metal discs c, between which are 
other metal plates d held on the sleeve e by 
means of a key f. The sleeve e is in turn keyed 



to the shaft g, and to it is screwed a ring h 
having three pairs of lugs carrying three levers i, 
with rollers j at their outer ends, as shown. The 
other ends of the three levers press against the 
plate k when the clutch is engaged by an in¬ 
ward movement of the collar 1, plate k being 
free to move along the key f. Discs c are free 
to move longitudinally on the arms of the spi¬ 
der a, and also on sleeve e, around which they 
rotate when the clutch is out of engagement; 
but the arms of the spider, fitting into slots in 
the discs, cause them to rotate with the shaft b. 












































216 


The Automobile Handbook 


The plates d are free to move longitudinally on 
the key f in the sleeve e; and since the sleeve is 
keyed to the shaft g, it is evident that, when 
in engagement with the discs c, the plates d 
must cause the shaft g to turn with the shaft b. 
The discs c and plates d run in an oil bath, 



obviating wear of the plates and discs. These 
are brought together forcibly by throwing the 
cone faced end of the collar 1 against the rollers 
j, thereby causing the ends of the three levers i 
to press the plates and discs together with suf¬ 
ficient force to cause the shafts b and g to rotate 
as one shaft. 






































The Automobile Handbook 


217 


Horse Power of Clutches. A simple for¬ 
mula for calculating the ordinary cone clutch 
is the following, by Charles H. S’chabinger: 

PfrR 

H. P. =-- 

63,000 sin 0 



00 

o 



P = Assumed pressure of engaging spring in 
pounds; 

f = Coefficient of friction, which in ordinary 
practice is about 0.25; 




















































218 


The Automobile Handbook 


r = Mean radius of the cone in inches; 

R = Revolutions of the motor per minute; 
sin 0 — Sine of the angle of the clutch. 

To obtain the size of spring when the horse¬ 
power is known, the following formula may be 
used with good results: 

h. p. 63,000 sin 0 

P =-— 

f r R 

the same symbols being used as in the preced¬ 
ing formula. It will be noted that the coeffi¬ 
cient of friction used is 0.25. This is probably 
near enough for a properly lubricated leather- 
iron clutch. 

Clutch Troubles. One of the greatest 
sources of trouble for the novice lies in the 
clutch. This may be just right, it may be slip¬ 
ping, or it may be what is called fierce. The sec¬ 
ond manifests itself in such pleasant situations 
as climbing a hill when, with the engine run¬ 
ning at its highest speed and the proper gear 
engaged, the car starts to run backward instead 
of forward. Or on the level, with the engine 
racing and the high gear in, no speed results. 

The last condition shows itself in the sudden 
jumping forward of the car when the clutch 
has been let in, or it may even be so severe as 
to shear off the bevel driving gear when used 
with studded non-skid tires or anv form that 
will not slip easily. 

To repair the first, look at the leather, if this 



The Automobile Handbook 


219 


is all in good shape with an apparently good 
surface, but has lubricating oil on it, wash the 
surface well with gasoline. It is not a bad idea 
to roughen the surface of the leather a little 
with a coarse tile. 

The harsh or fierce clutch is remedied by the 
application of a proper oil for this purpose. 
Castor oil is universally used and a good way is- 
to soak the complete clutch in it over night. 
This will cure a case of harsh leather, but it 
may be that the trouble is only a lack of adjust¬ 
ment of spring tension. Usually there is an ad¬ 
justing nut and a locking nut. Back off the 
latter and make an adjustment. Then tighten 
the lock nut to retain it. For the beginner, it 
is better to adjust a little at a time and make 
several successive jobs of it than to try to do 
it all at once. But always adjust it as soon as 
possible. 

The leather of the ordinary cone clutch by 
degrees acquires a sort of coarse surface glaze, 
which may or may not represent actual charr¬ 
ing of the leather, but is certainly due to the 
slipping it experiences. A leather with its sur¬ 
face so glazed has a very harsh action, since the 
surface is so hard that it grips all at once. The 
glazed surface will not absorb oil to any appre¬ 
ciable extent, a fact which is easily seen on at¬ 
tempting to dent the surface with a thumb nail 
after giving the oil time to soak in. In this con¬ 
dition the best thing to do is to put on a new 
leather. Unless the angle of the cone is too 


220 


The Automobile Handbook 


abrupt, a piece of ordinary belting will serve 
the purpose, provided it is of uniform thickness 
throughout. The belting may be soaked in 
neatsfoot oil over night before applying, and 
this will render it pliable enough to take the 
shape of the cone. If the old leather is retained 
in service it becomes almost essential to squirt 
a little oil on it every day or two, as otherwise 
it may take hold with such a jerk as to endan¬ 
ger the transmission shafts. If the cone re¬ 
leases by drawing backward, there are proba¬ 
bly openings in the web of the cone through 
which the spout of a squirt can may enter. Oil 
squirted into the flywheel interior will then 
quickly 'find its way to the clutch surface. 
Sooner or later, however, the leather will be¬ 
come glazed so smooth that it will not hold at 
all. and it is then liable to slip and burn up 
without warning. There are few things more 
exasperating than a clutch which cannot be 
made to hold properly, particularly when the 
car happens to be covering a bad stretch on 
which every available bit of power that can be 
transmitted to the rear wheels is necessary. The 
use of emergency remedies under such circum¬ 
stances most often leads to the necessity for 
clutch repairs, as road dirt and grit are not the 
best things possible for the leather facing, and 
frequently no other friction producing com¬ 
pound is to be had at the time. 

Renewal of Leather on Cone Clutch. Re¬ 
move the old leather by cutting off the rivets 


The Automobile Handbook 


221 


on the underside, and driving the rivets through 
to the outside. Keep the old leather and use 
it as a pattern by which to cut the new piece. 
It, will be much better, however, to purchase 
from the factory a new leather of the proper 
width and thickness. As a new leather will 
have considerable “give,” it must be stretched 
tightly over the cone. First cut one end of the 
leather square and fasten it to the cone with 
two rivets. The other end should not be cut at 
this stage of the work, but brought around to 
meet the fastened end, and, after tightly 
stretching it over the small end of the cone, 
fasten it with a single rivet. Then force the 
leather up onto the cone, drill out and counter¬ 
sink the holes and rivet up securely. The only 
knack in the operation is to keep the leather 
tight that it may be a snug fit on the cone. A 
loose leather will, naturally, be a dead failure. 
After the leather has been forced into its place 
the uncut end should be trimmed to make a 
good joint. Any unevenness may be trued up 
with a file. The new leather will readily ab¬ 
sorb several applications of castor oil before it 
becomes smooth and pliable. 

Care should be taken that the rivet heads are 
countersunk below the surface of the leather. 
In case they work flush, owing to the wearing 
down of the leather face, they should be riv¬ 
eted. The “biting” or jerky action of a cone 
clutch may often be traced to the rivets work¬ 
ing out, and this will frequently prevent the 


222 


The Automobile Handbook 


clutch from being readily disengaged. Rerivet¬ 
ing will prove an effective remedy in this case, 
and considerable additional service may be had 
from the leather before it wears down to the 
rivet heads. 

Combustion Chamber. That part of an ex¬ 
plosive motor in which the gases are com¬ 
pressed, and then fired, usually by an electric 
spark, is known as the combustion chamber. 
The interior of the combustion chamber should 
be as smooth as possible and kept free from 
soot, or hard carbon deposits such as are in¬ 
duced by excessive lubrication, or the use of too 
rich an explosive mixture. 

It will be found to be no small task in design¬ 
ing an explosive motor with the usual form of 
valve construction and operation, to keep the 
combustion chamber down to the required di¬ 
mensions and at the same time have it free from 
bends or contracted passages between the com¬ 
bustion space and the valve chamber. 

Many attempts have been made to obviate 
this difficulty by making the combustion cham¬ 
ber simply a straight extension, or continuation 
of the cylinder. In this manner both the ad¬ 
mission and exhaust-valves can be placed in the 
cylinder itself and an ideal combustion space 
secured. This plan has, however, certain dis¬ 
advantages, from the fact that it not only 
lengthens the motor, but requires a more com- 
nlicated form of valve operating mechanism 


The Automobile Handbook 


than if the valve chamber were at the side of 
the cylinder as is usual. 

Combustion Chamber, Dimensions of. If it 
is desired to ascertain the cubic contents or di¬ 
mensions of the combustion chamber of an ex¬ 
isting motor, they may be found by filling the 
combustion space with water, then obtaining 
the weight of the water in ounces, which multi¬ 
plied by 1.72 will give the capacity of the cham¬ 
ber in cubic inches. If a motor is to be de¬ 
signed with a given bore and stroke, the first 
thingato do is«to decide on the amount of clear¬ 
ance or combustion space at the end of the cyl¬ 
inder for the gases to occupy after compression. 

If the combustion space could be made as a 
continuation or extension of the cylinder bore, 
it would be an easy matter to determine the re¬ 
quired clearance, as it would simply be some 
fraction of the total piston stroke. 

But as the general design of a combustion 
chamber deviates widely from a plain section or 
length of a cylinder as above described, being 
in some cases flat, oval, elliptical, semi-spheri¬ 
cal and even rectangular in cross section, some 
other method must be used to calculate the re¬ 
quired clearance. 

To do this correctly the contents of the com¬ 
bustion chamber in cubic inches must first be 
ascertained, and then apportioned between the 
valve chamber or chambers and the clearance 
proper which lies directly behind the piston 
head. 


224 


The Automobile Handbook 


To find the cubic contents of a combustion 
chamber when the degree of ocmpression in 
atmospheres is known: Let S be the stroke of 
the piston in inches and A the area of the cyl¬ 
inder in square inches. If N be the number of 
atmospheres compression and C the required 
contents of the combustion chamber in cubic 
inches, then 

SX A 

C =-- 

N —1 

Example: Find the cubic contents of the 
combustion chamber for a motor of 4-inch bore 
and 5-inch stroke with 4 atmospheres compres¬ 
sion. 

Answer: Five multiplied by 12.56 equals 
62.83, which divided by 3 gives 20.94 as the 
number of cubic inches required. 

Commutators, Care of. Commutators with a 
make and break form of contact-maker, should 
have the platinum contacts cleaned at least once 
a week, with a small piece of fine sandpaper. 

Commutators having a rotary wiping form of 
contact, should have the brass or copper seg¬ 
ment thoroughly cleaned in the manner just 
described, and all grease or dirt removed from 
the fiber portion of the commutator. 

All thumb or lock-nuts and adjusting screws 
should be carefully gone over, and the condition 
of the wiring from the battery and coils exam¬ 
ined very closely. Ten minutes spent in this 



The Automobile Handbook 


225 


manner once a week may save long delays and 
much laborious work at some future time. 

Commutators, Forms of. The commutator 
of the ignition system of a multi-cylinder gaso¬ 
line motor has a three-fold use: To switch the 
battery current in and out of the electrical cir- 
cuit at the proper time—To transfer the bat¬ 
tery current successively from one coil to an¬ 
other—To vary the point or time of ignition 
of the explosive charge in the motor cylinder. 



The commutator shown in Figure 109 is for 
a four-cylinder motor and is designed for use 
with induction coils without vibrators, which 
are known as single-jump spark coils. The 
studs of the screws A and springs B are car¬ 
ried by insulated bushings located in the back 

i 

of the commutator case. The nose of the earn 
C successively engages with the springs, caus¬ 
ing them in turn to make contact with their 
respective screws. The battery and coil circuit 
is completed through the screws A, and a 








226 ' The Automobile Handbook 

ground to the cam C, by means of the springs 
B, when in contact with their respective screws 
and the cam. 

This device is said to cause a good spark at 
the plug on account of the quick break between 
the spring and the screw, the electrical circuit 
being broken the instant the spring leaves the 
screw and before the cam lias allowed the 
spring to resume its normal position. This form 
of commutator cannot be short-circuted by oil 


Fig. 110 



or dirt getting between the spring and the 
screw, as the spring B only forms a part of the 
electrical circuit when in contact with both the 
cam C and the screw A. 

Another form of commutator for a four-cyl¬ 
inder motor is illustrated in Figure 110, which 
has a rotary spring contact-maker A, which 
engages successively with the heads B of the 
screws C. The screws are spaced equidistant 
around the fiber ring D, which also forms the 
case of the commutator, and are held in position 





The Automobile Handbook 


227 


by the locknuts E. The spring contact-maker 
A is attached to a hub F on the cam shaft of 
the motor. The time or point of ignition may 
be varied by moving the commutator case about 
its axis by means of a rod attached to the 
arm G. 

Figure 111 shows two commutators of very 
similar construction. The one at the left in the 
drawing is for a two-cylinder motor, and has 
flat spring-steel contact-makers. The comnm- 



Fig. Ill 


tator shown at the right of the drawing is for 
a four-cylinder motor and instead of having flat 
spring contact-makers, it has either carbon or 
copper contact-brushes, which are held against 
the commutator by short coil springs in the in¬ 
sulated bushings located around the periphery 
of the commutator case. The commutator is 
made of vulcanized fiber with a short brass or 
or copper segment, which is grounded to the 
cam shaft as shown. 












228 


The Automobile Handbook 


The forms of commutators illustrated in the 
drawings may be constructed for use with a 
motor of any number of cylinders, by increas¬ 
ing or decreasing the number of contact-mak¬ 
ers located around the commutator. 

Compensating Joints. On account of the 
distortion of the frame or running gear of an 



Fig. 112 


automobile, due to unequal spring deflection 
and irregularities of the road surface, means 
should be provided to insure flexible joints or 
connections between the various rotating parts 
of the mechanism of a car. The device shown 
in Figure 112 is not susceptible to any great 
amount of angular distortion, but will transmit 
power with a practically uniform velocity, with 



























































The Automobile Handbook 


229 


tlie axes of the shafts considerably out of align¬ 
ment in vertical or horizontal parallel planes. 

The form of compensating joint shown in 
Figure 113 may be operated with the axes of 
the shafts at an angle to each other, or with the 
shafts out of alignment with each other in ver¬ 
tical or horizontal parallel planes, and has quite 
a range of operation with either condition. Both 


f\ ° i ) 
„ J .i... 


_, 


i— r~ p 










o 


j ®i 

o 






1 1 1 V s 






_i_i_ U 



r°D 


r-AJJ 


-- 



I IK 





• 



1 m) 

i i\_-/ 


1 

I 

l 

(i)\ 

• 




l 1 w 

i 1 1 






COMPENSATING JOINT 

Fig. 113 

forms of the device require to have bearings on 
either side, as shown, to insure their proper 
working. 

Compression. Normal compression in any 
given design of motor would be the compres¬ 
sion (cold) fixed by the designer by the rela¬ 
tion of the sweep of the piston to the clearance 
space. Normal compression is not the same, as 



























































230 


The Automobile Handbook 


measured in pounds per square inch, in all mo¬ 
tors. The normal compression as against loss 
of compression would be evident to a motorist 
in the act of cranking. Were the compression 
to become abnormal, as a result of carbon de¬ 
posit, it would be rendered manifest by knock¬ 
ing on a gradient, or by way of pre-ignition. 

The cold compression can be found by means 
of a gauge reading to about 90 pounds per 
square inch. Screw the gauge into the threaded 
hole, normally used for the spark plug. An¬ 
other way is to use a spring balance, hooked 
to the starting crank, and by a steady up puli, 
against the compression, the pull in pounds re¬ 
sultant of the compression may be noted. 

Allowable Compression. Assuming that the 
design is good and that a motor is in proper 
working order, the allowable compression de¬ 
pends upon several factors as follows: 

(1) If liquid gasoline is entrained, upon the 
latent heat of evaporation of the liquid, of 
which gasoline is composed considering its com¬ 
plex character. 

(2) The specific heat of the mixture, which 
will differ as the composition changes, it being 
the case that all the contents entering into mix¬ 
tures are not of the same specific heat. 

(3) The extent of scavenging, and the heat 
of the spent products of combustion, in the ab¬ 
sence of complete scavenging. 

(4) The temperature of the water in the w r a- 
ter-jacket, or the efficiency of the air-cooling 


The Automobile Handbook 


231 


process, if air is used direct for purposes of cool¬ 
ing. 

(5) The design of the cylinders, and the ex¬ 
tent to which the surfaces maintain an even 
temperature; if some one zone on the surfaces 
is at a high heat, pre-ignition will follow, it be¬ 
ing the case that this heated zone will be at the 
bottom of the trouble, nor does it matter if the 
zone is of small area. This trouble is most likely 
in cylinders of relatively large bore, in which 
the piston is likely to heat up at the axis of the 
head, which is the greatest distance away from 
the cooling medium, and it generally is the part 
in which the heat conductivity is a minimum 
because the metal is coated with a crust, due 
to elevated temperature, and the metal in the 
head is thin in order to have the piston as light 
as possible. 

(6) If the valves are not properly water- 
jacketed they are likely to heat above the de¬ 
sired temperature, and pre-ignition will be due 
to such over-heat. 

(7) In some cases to make the motor as 
short as possible the water-jacket is so designed 
that but little of the cooling liquid will circu¬ 
late over the dome of the combustion chamber, 
which is just the part that requires the greatest 
amount of cooling, and pre-ignition will be emi¬ 
nent in all such cases. 

(8) Fins, seams, protuberances, etc., due to 
defective designing, or misplaced cores in the 


232 


The Automobile Handbook 


foundry process, will heat up and they will be 
the direct cause of pre-ignition. 

(9) If the water ciculation is not good, or if 
the amount of water circulated is inadequate, 
pre-ignition will follow. In some cases the 
water is enabled to short-circuit across from 
the. inlet to the outlet without passing over the 
hot surfaces, and this a prolific cause of pre¬ 
ignition. 

(10) Increasing compression tends to in¬ 
crease the terminal pressure, thus allowing and 
engendering an increase in speed of the motor 
without pre-ignition because the conditions of 
scavenging improve as a result. 

(11) Running on a “retarded” spark results 
in over-heating, and pre-ignition is likely to fol¬ 
low if the other (remaining) conditions are fa¬ 
vorable. 

(12) Running on a mixture that is too rich 
will cause excess heating, which is indicated by 
a steaming cooler, and pre-ignition is likely to 
be one of the manifestations. 

Although the compression of the charge dur¬ 
ing the second stroke requires the abstraction 
of considerable power from the fly wheel, the 
work done upon the charge in compressing it 
is more than returned, during the power stroke. 
It is therefore found that with a high degree of 
compression, a high fuel economy is obtained, 
and a large output is secured from a motor of 
relativelv small size. 

Much of the increased power for equal cvlin- 


The Automobile Handbook 


233 


der capacity is due to compression of the 
charge, because the most powerful explosion of 
gases takes place when the particles are in Clos¬ 
est contact. 

Another advantage of a high compression mo¬ 
tor is that on account of the smaller clearance, 
less cooling water is required than with a low 
compression, as the temperature, and conse¬ 
quently the pressure, falls more rapidly. The 
loss of heat through the water jacket is thus 
less in a high compression than in a low com¬ 
pression motor. 

The difficulty about obtaining high compres¬ 
sion is that if the pressure is too high, the 
charge is likely to ignite prematurely, as com¬ 
pression always results in increased tempera¬ 
ture. 

Limits of Compression. With gasoline vapor 
and air, the compression cannot be raised much 
above 85 pounds per square inch, but with 
the heavier fuels, such as kerosene, a com¬ 
pression as high as 250 pounds per square inch 
has been used economically. It has been the 
advantages of high compression that has turned 
the designer of automobiles toward the heavier 
fuels; but, with the increase of compression, 
there are many troubles in regard to loss of 
power and increased fuel consumption, owing 
to the wear of the valves, pistons and cylinders, 
which produces a loss in compression and ex¬ 
plosive pressure, and a waste of fuel by leakage. 

Compression, ITow to Calculate. The com- 


234 


The Automobile Handbook 


pression in atmospheres of a motor may be read¬ 
ily found by dividing the cubic contents of the 
piston displacement by the cubic contents of 
the combustion chamber in cubic inches, and 
then adding one to the result. 

To ascertain the compression in atmospheres 
of a motor, when the cubic contents of the com¬ 
bustion chamber are known: Let S be the 
stroke of the piston in inches and A the area of 
the cylinder in square inches. If C be the con¬ 
tents of the combustion chamber in cubic inches 
and N the required compression in atmospheres, 
then 

S' X A 

N= - +1 

C 

Example: Find the compression in atmos¬ 
pheres of a motor of 4-inch bore and 6-inch 
stroke, whose combustion chamber has a capac¬ 
ity of 18 cubic inches. 

Answer: Six multiplied by 12.56 equals 

75.36, which divided by 18 gives 4.19, and 4.19 
plus 1 equals 5.19, or the compression in at¬ 
mospheres required. One atmosphere = 14.75. 

If it is desired to ascertain the compression 
in atmospheres of a motor, the combustion 
chamber of which is of such shape that its di¬ 
mensions cannot be accurately calculated, its 
cubic contents may be found by filling the com¬ 
bustion chamber with Avater, and after remoA^- 
ing the water, ascertaining its Aveight in ounces, 



The Automobile Handbook 


235 


and then multiplying the result by 1.72. This 
gives the capacity of the combustion chamber 
in cubic inches. The compression of the motor 
can then be readily calculated from the for¬ 
mula given herewith. 

Compression, How to Test for Leaks in. To 
discover if there are any leaks in the compres¬ 
sion of a gasoline motor, a small pressure gauge 
reading up to 75 pounds should be fitted into 
bhe spark plug opening in the combustion 
chamber by means of a reducing bushing. When 
turning the starting crank of the motor slowly 
the gauge should indicate at least 60 pounds 
per square inch if the compression is in good 
condition. 

To test for leaks, fill a small oil can with 
soapy Avater and squirt round every joint where 
there may be a possible chance for leakage. Get 
an assistant to turn the crank and watch for 
bubbles at the joints. 

If the joints are all tight, next examine the 
condition of the admission and exhaust-valves 
and if either of them needs regrinding, it 
should be done, first with fine emery poAvder 
and oil, then finished Avith tripoli and Avater. 

When the valves have been ground to a per¬ 
fect fit, if the compression still leaks, the pis¬ 
ton rings should be examined, as the trouble 
Avill be found to be with them. 

Condenser, Use of. A condenser is used in 
connection with a Kumkorff, or jump-spark 
form of induction coil to take up or absorb the 


236 


The Automobile Handbook 


static charge of electricity,, occasioned by the 
self-induction, or electrical reaction in the pri¬ 
mary winding of the coil upon the breaking of 
the battery circuit by the interrupter or vibra¬ 
tor. This static charge is given up or dis- 



Fig. 114 
Condenser 

charged into the primary winding of the coil 
along with the battery current upon the closing 
of the circuit, thus intensifying the action of 
the secondary winding of the coil in a great de¬ 
gree. 

By absorbing the static charge of electricity 






















































































































The Automobile Handbook 


237 


the condenser helps to decrease the spark or arc 
between the platinum contact points of the in¬ 
terrupter or vibrator, thereby lengthening- the 
life of the platinum contacts by reducing the 
erosive action of the induced current spark. A 
jump-spark coil very often refuses to work 
properly on account of the condenser connec¬ 
tions having become loose. 

The capacity of a condenser is directly pro¬ 
portional to the area of the tinfoil sheets com¬ 
posing it, to the distance between the sheets, 
and to the inductive capacity of the dielectric, 
or separating medium. 

In condenser work it is the custom, to cut the 
tin-foil sheets to some convenient rectangular 
shape, as shown in Fig. 114, each one with a 
neck so that all the + sheets can be soldered to¬ 
gether, on one side, and all the — sheets on the 
other. The dielectric paper is cut without 
necks, so that the necks of the tin-foil sheets 
can be readily contacted with each other, in 
such a wav, however, that the + sheets will 
not contact with the — sheets at any point. 
The paper is 1 inch wider than the tin-foil, so 
that the paper extends out for % inch all 
around, and beyond the tin-foil. In the illus¬ 
tration the top sheet of paper is removed to 
show the shape of the tin-foil sheets, and it will 
be observed that all the tin-foil sheets are of 
the same size, but they are so turned that the + 
sheets have their necks all to one side, while 
the — sheets have all their necks to the other 


238 


The Automobile Handbook 


side. Any number of sheets can be used, with 
the understanding that a sheet of oil-paper will 
be placed between adjacent tin-foil sheets, so 
that the + and — sheets will not contact with 
each other at any point. 

If the paper is pierced, or if the -f- and — tin- 
foil sheets contact with each other, the con¬ 
denser will fail to perform its functions, and it 
sometimes happens that the sheets are punc¬ 
tured in service, thus rendering the condenser 



Fiff. 115 

o 


valueless for the intended purpose until the 
puncture is repaired, to do which requires that 
the fault be found, and a new sheet of paper 
substituted. 

Constant Speed. One of the best lessons in 
the proper method of driving a car is that of 
driving at a constant speed, no matter what the 
road conditions. The autoist should previously 
determine a speed compatible with the nature 
of all roads over which the car is to pass, and 





















The Automobile Handbook 


239 


should see that the speedometer hand keeps at 
the determined speed throughout, regulating 
the spark and throttle and changing gears if 
necessary. Considerably more will be learned 
about the flexibility and power of the motor in 
driving in this way for a few times in numerous 
drives in the ordinary way. 

Contact-breaker. Some forms of high speed 
gasoline motors with an induction coil of the 
single-jump-spark type, have a device known as 
a contact-breaker to open or break the electric 
circuit of the battery and coil, at the proper 
time for the passage of the arc or spark at the 
points of the spark plug. On account of the 
extremely high speed of such motors, and to 
allow time for the magnetism or magnetic flux 
in the core of the coil to attain a density suf¬ 
ficient to produce a good spark at the plug 
points, it is found necessary to keep the battery 
and coil in a closed circuit, except during the 
brief interval necessary for the passage of the 
spark at the plug points. 

Figure 115 illustrates one form of contact- 
breaker. The left-hand end of the double lever 
is kept in contact with the lower end of the 
insulated pin, by means of a short spring 
immediately below it. When the nose of the 
cam engages with the roller in the fork or jaw 
at the right-hand end of the double lever, in¬ 
stant separation of the nose of the insulated 
pin and the left-hand end of the double lever 
takes place, breaking the electric circuit and 


240 


The Automobile Handbook 


causing a spark to occur at the points of the 
spark plug. 

The electric circuit of the battery and coil is 
completed by one wire being connected with 
the lock-nuts on the upper end of the insulated 
pin and the other wire grounded on the case of 
the contact-breaker. 

Contact-maker. One of the simplest methods 
of electric ignition for explosive motor use is 



that known as the single-jump-spark system, 
with which a plain induction coil without a vi¬ 
brator or trembler is used. The secondary spark 
is produced by means of a mechanical device 
operated by the cam shaft of the motor. The 
devices illustrated, and which are known as con¬ 
tact-makers, cause a spark to arc or jump be¬ 
tween the points of the spark plug in the com¬ 
bustion chamber of the motor. 



241 


The Automobile Handbook 

Figure 116 shows one form of contact-maker. 
The case A is usually attached to the gear box 
of the motor. Attached to a boss on the inside 
and near the upper end of the case is the trem¬ 
bler B, consisting of a flat steel spring with a 
nose at its lower end. Near the center of the 
spring is a platinum contact-point C. On the 
opposite side of the case is a bushing with in¬ 
sulation E, carrying the screw D, which is so 
adjusted that it does not quite contact with the 
platinum point C of the trembler. As the cam 
F revolves in the direction indicated by the ar¬ 
row, it comes in contact with the nose of the 
trembler B, and pushes the platinum point C 
still further away from the screw. Shortly 
before the cam has arrived at the position 
shown in the drawing, it has released the nose 
of the trembler, allowing it to fall; this action 
produces a vibrating effect, opening and clos¬ 
ing the circuit repeatedly and with great rap¬ 
idity, between the point C and screw D. 

This is supposed to cause a stream or succes¬ 
sion of sparks to occur between the plug points 
in the combustion chamber of the motor. In 
practice, however, and at a high rate of speed, 
only a single spark occurs. 

Another form of contact-maker is shown in 
Figure 117. The trembler B has a small roller 
upon its lower end which at the proper time 
is engaged by the nose of the cam F. The 
screw D is carried in a metal block I, which is 
attached to the back of the case A by suitable 


242 


The Automobile Handbook 


insulating bushings E. The screw H in the in¬ 
sulated bushing at G, makes the electrical con¬ 
nection from the coil and battery, through the 
block I and screw D, to the platinum contact 
C on the trembler B. The operation of this de¬ 
vice is precisely the same as that of the one 
shown in Figure 116. 



Fig. 117 


Cooling Systems. The cooling of a gasoline, 
or other automobile engine may seem a simple 
thing to the uninitiated, but in reality it is far 
from that and it is a fact that the deeper one 
goes into it, the more complex the situation be¬ 
comes. 

The cooling of internal combustion engines 
in which category, automobile engines come, is 



The Automobile Handbook 



divided into two classes, viz., air cooled and 
liquid cooled. There are two reasons for cool¬ 
ing’ the cylinder walls. One is to permit of 
proper lubrication, and the other is to prevent 
pre-ignition. But it is advisable to allow the 
cylinder to work at as high a temperature as 
the lubricating oil will stand without carboniz¬ 
ing. The nearer the cylinder temperature can 
be kept to 350 degrees the more efficient will 
the motor be, speaking from the thermal stand¬ 
point, while on the other hand, mechanical effi¬ 
ciency may be sacrificed by too high tempera¬ 
tures. Therefore a balance between the two 
should be established, and this course is usually 
pursued in practice. 

Cooling Solutions—For Winter. Radiators 
are costly, delicate and composite in construc¬ 
tion, the latter due to the plurality of metals in 
their make-up, hence electrolytic action takes 
place, due to the difference of potential nat¬ 
ural to the different metals immersed in a saline 
bath. Therefore great care should be exer¬ 
cised in the preparation of anti-freezing solu¬ 
tions made up of calcium chloride (common 
salt) and water. Any approach to the satura¬ 
tion limit is attended with danger of precipita¬ 
tion. The saturated solution is ascertained at 
60 degrees F., and increasing the temperature 
increases the capacity of the water to hold the 
salts in suspension. 

On the other hand, the Ohmic resistance of 
a solution is lowest at about half saturation. 


244 


The Automobile Handbook 


To sum up, it is experience that counts, and 
it is still a question as to the extent to which 
saline solutions can be used with safety. Of 
course there is no solution as good as water 
alone, but unfortunately water will expand 
when it freezes, and it will freeze on small pro¬ 
vocation in a radiator. Oil as a cooling medium 
has points in its favor which some authorities 
claim render it more efficient than water, as 
for instance it has a higher boiling point, about 
double that of water, and as a result the oil 
will not waste away except by leakage. The 
heat exchange occurs at a higher temperature, 
thereby increasing the efficiency of the motor. 
Then also the area of radiating surface may be 
smaller, with a conesquent decrease in weight, 
while the work of the fan is rendered of less 
importance. A light, thin, pure mineral oil is 
the most reliable. Animal, and vegetable oils 
are more apt to become rancid, the acid in them 
also attacks the metal of the radiator. 

Alcohol, or a mixture of alcohol and glycer¬ 
ine, also are serviceable. With the former a. 
temperature of 30° below zero, F., can be with¬ 
stood, while the latter gives better service at 
temperatures ranging around 15° below zero. 
The following table gives the different tempera¬ 
tures at which these mixtures will freeze: 


Per cent by 
Weight 
25 
30 
35 
40 
45 


ALCOHOL 

Freezing Point 
Fahr. 

-3 

-9 

-16 

-25 

-36 


The Automobile Handbook 


245 


Cylinders Worn. Almost all the wear comes 
on the side against which the piston is forced 
by the angularity of the connecting rod during 
the lower stroke. Moreover, the wear is likely 
to be greatest in the middle of the piston's 
travel, particularly if the piston wall has not 
been relieved at its middle portion to concen¬ 
trate the pressure at the ends. For this reason 
it is not enough, when a cylinder is suspected 
of being out of round, to caliper across two di¬ 
ameters at right angles to each other. It must 
also be calipered at the top, middle and bottom 
of the piston’s travel. If the cylinder is worn 
oval to about the same extent throughout the 
piston’s travel, it is still possible for the rings 
to fit after a fashion, but if when the rings fit 
tightly at one portion of the stroke they are 
open at another portion, leakage inevitably re¬ 
sults, and it is time to re-grind, the cylinders. 
If the diameter of the cylinder is not increased 
more than two or three-thousands it is possible 
that, the old piston can be used by simply fitting 
new rings. A greater enlargement, however, 
requires for durability and quiet running that 
a new piston be made and fitted. The location 
of valves and design of the cylinder head has 
quite a little to do with the wearing of the 
walls, this being due to the peculiarities in ex¬ 
pansion due to contour. 

Cylinder Oil Testing. There are really two 
parts to the fire test, as it is called. One is the 
test for flash point. This may be determined 


246 


The 'Automobile Handbook 


as follows: Take two pieces of glass of the 
same size, and large enough to cover a small 
glass beaker. In one of them cut a couple of 
notches. These are for two purposes. One is 
for the thermometer and the other for the flash 
point determination. Insert a thermometer in 
the beaker, filled with the oil under test. Place 
the notched glass over this and the other piece 
of glass over that, taking care to cover the 
notch not in use. Now uncover this notch, note 
the temperature, and apply a lighted match to 
the opening. If nothing results, warm the oil 
slowly over a flame to a higher temperature 
and take another trial and reading. Continue 
the test until upon the application of the 
lighted match the oil vapor over the oil flashes. 
The thermometer reading at that point gives 
the flash point. The glass plates may now be 
removed, and heating continued. The match is 
applied at similar intervals, until finally the oil 
burns, which will usually occur at about 50 de¬ 
grees above the flash point. 

An additional test is for precipitation at a 
known temperature. This is also made in a 
beaker. Two ounces is the usual amount. It 
is heated to the desired temperature, at which 
the oil may change color, but must not show a 
precipitation. Still another good oil test is the 
evaporation test. This is the result of slow 
heating, and the usual specification is that the 
oil shall not lose over 5 per cent, of its volume 
when heated to 150 degrees Fahr. for 12 hours. 


The Automobile Handbook 


247 


Flash point, burning point and precipitation 
vary with the service for which the oil is in¬ 
tended, thus air-cooled motors always require 
a much higher oil test than those for water- 
cooled machines. As this is some indication of 
the quality, it is higher priced and harder to 
obtain, both in purity and evenness, and as a 
matter of convenience. Three hundred degrees 
is about the lowest flash point that should be 
accepted. With this would go 350 to 400 burn¬ 
ing point and about 500 precipitation lower 
limit. In fact, oils may be had for any desired 
flash point and burning point up to 450. Be¬ 
yond that they are hard to obtain. It is fre¬ 
quently claimed that this, that or the other oil 
will test 800 degrees, meaning the burning 
point. In the face of this statement, a simple 
home test as outlined above will determine at 
once the quality of the oil. 

Dalton’s Laws. The relation between the 
vapor tension and the quality of vapor is ex¬ 
pressed by two laws known as Dalton’s laws, 
as follows: 

I. The pressure, and consequently the quan¬ 
tity, of vapor that will saturate a given space 
are the same for the same temperature, whether 
the space contains a gas, or is a vacuum. 

II. The pressure of the mixture of a gas and 
a vapor is equal to the sum of the pressures that 
each would exert if it occupied the same space 
alone. 

If a volatile liquid is added to a gas, and the 


248 


The Automobile Handbook 


resulting mixture of gas and vapor is allowed 
to expand so that the pressure remains un¬ 
changed, the volume of the mixture will exceed 
the original volume of the gas. The ratio of 
this new volume to the original volume of the 
gas is equal to the ratio between the combined 
pressure of the gas and vapor, and the pressure 
of the gas alone, had the volume remained con¬ 
stant. 

Deposits in Water Jacket. If the cooling 
water contains lime or alkali, the heating of the 
water in the jacket will cause these solid sub¬ 
stances to be deposited in the cooling spaces. 
This will soon choke any narrow ports and pre¬ 
vent proper circulation, resulting in overheat¬ 
ing, rapid wearing of the valves, and loss of 
power and efficiency. A simple remedy consists 
of the application, at regular intervals, of a di¬ 
lute solution of hydrochloric, or muriatic, acid, 
made as follows: Dilute one part of muriatic 
acid with nineteen parts of water, and, after 
draining the jacket completely, pour in enough 
of the solution to fill the entire cooling space. 
Allow the mixture to remain in the jacket for 
not more than 8 to 12 hours, after which wash 
the cooling space thoroughly by running clear 
water through it. If the solution is permitted 
to remain in the jacket longer than the period 
stated, there is danger that the metal may be 
damaged by the action of the acid. The acid 
will soften and dissolve the lime or alkali, and 
the clean water will remove it from the jacket. 


The Automobile Handbook 


249 


It is generally sufficient to apply this method 
of removing the deposits once every two weeks. 
If neglected too long, the acid will not dissolve 
the deposit. 

Differential Gears. So long as an automo¬ 
bile moves in a perfectly straight path, its two 
driving wheels turn at equal speed, since they 
must cover equal distances in equal periods of 
time, and it would be perfectly allowable that 
the two wheels should be locked together, as 

there would be no relative motion between 

* 

them. The power could be transmitted to 
either one, or to both of them with perfectly 
satisfactory results under these circumstances. 

When, however, a car is to be moved in a curved 

« 

path, as in turning a corner, the driving wheels 
must move at different speeds, since the out¬ 
side one has to cover a longer distance in the 
same time than does the wheel which is on the 
inside of the curve. If the two wheels were 
locked together under these conditions, one or 
both of them would be forced to slip, as the 
speeds transmitted to them would be equal, 
while the distances they are to travel are un¬ 
equal. This difficulty is successfully overcome 
by the use of the differential gear which trails- 
mits the power from the change-speed gear to 
the rear axle, or driving wheels of the car. 
Differential gears consist of a set of four or 
more gears attached to the ends of two shafts 
that meet, and are usually in line, so that 
both are rotated in the same direction. But, if 


250 


The Automobile Handbook 


either meets with extra resistance it may rotate 
more slowly than the other, or may stop alto¬ 
gether. 

These gears are used on the driving axles 
of automobiles. The axle is made in two parts, 
with a gear on the end of each, where the parts 
come together. Other gears mesh with both 
these axle gears, and are driven from the engine 
by a sprocket and chain, or by bevel gears and 
shaft. These gears turn the axle, but permit 
its two parts to turn in respect to each other 
so as to allow the automobile to go around a 
corner without causing the wheels to slide, or 
skid. The rear wheels are each fixed to a half 
of the rear axle, and both receive power, 
hence it is necessary to allow one wheel to turn 
at a different speed from the other, and this 
is accomplished by means of the differential 
gear. 

Bevel Gear Differential. Fig. 118 shows 
a semi sectional view of the bevel differential 
gear. The engine shaft carries a bevel gear 
wheel shown in section at a. This gear meshes 
with the large bevel gear b, on the differential 
gear case c. On the inside of this gear case 
are carried a number of small bevel gears, one 
of which is shown in section at d. These are 
free to turn on the studs that hold them to the 
gear case. These gears in turn mesh with bevel 
gears e and f, on the ends of the half axles. 

The principle governing the action of the 
bevel gear differential is similar to that of tV» 


The Automobile Handbook 


251 


spur gear differential. When the two bevel 
gears e and f on the half axles meet with the 
same resistance, the small bevel gears d do not 
turn on their bearings; but when the movement 
of one of the gears e or f is resisted more than 



that of the other it lags behind, causing the 
small bevel gears d to turn on their axles suffi¬ 
ciently to equalize the resistance. 

Spur Gear Differential. In the spur dif¬ 
ferential, bevel gears are replaced by gears of 










































































252 The Automobile Handbook 

the spur type, as shown in Fig. 119, a large 
spur gear being secured to each half axle, as 
shown at A and B, exactly as are the bevel 
gears. A double set of spur pinions, E and F, 
having their bearings in the frame, revolve 



upon axes parallel with the axle. For each 
bevel pinion is substituted a pair of spur gears, 
E and F, which mesh with each other, and at 
the same time each one of them is in mesh with 
one of the large gears. The combination of the 





























The Automobile Handbook 


253 


motion of each pinion of the pair upon its gear, 
and the motion of the pair upon each other 
produces the same effect as the use of a bevel 
pinion. When the vehicle is rounding a curve, 
one rear wheel moves less rapidly, causing the 
pinions with which it is geared to revolve upon 
their bearings, and thus compensate for the in¬ 
creased resistance. 



Fig. 120 

Russel’s Gearless Differential 


Russell’s Gearless Differential. The ac¬ 
tion of this device as described by the inventor, 
H. M. Russell, is as follows: On the half axles 
A, Fig. 120, are cranks B, one on each. The 
usual sprocket case C, with sprocket S, carries 
a pin J diametric to the case, but at right angles 
to the axis of the vehicle. On this pin is a ring D, 
Fig. 121, journaled so that it may make nearly 
a half revolution on the pin, and having its two 






















254 


The Automobile Handbook 


free sides slotted at H to receive the crank 
pins. A peculiarity of the cranks B is that 
they are arc-shape and in certain positions lie 
concentric with the ring D, while their crank- 
pins P are not parallel with the rear axle 
which is the main shaft in this case, but are 
radial to the center of the ring D and case G. 
The ring serves to send half the power to each 



Fig. 121 

Russel’s Gearless Differential 


crankpin P just as did the bevel pinion. A 
little thought will show that the ring will trans¬ 
mit no power when the crankpins P are moving 
lengthwise the slot H, as they will be when at 
right angles to the ring pin. A second ring 
therefore is placed inside the first and the slots 
are cut at an angle to each other, D 1 , Pig. 121. 
By this arrangement any position of a crankpin 























The Automobile Handbook 


255 


cm one side must be met by the pin on the other 
side so the balance is maintained. 

Again referring to Fig. 120, it will be seen 
that since the center planes of the slots H also 
pass through the center of the device, the mech¬ 
anism will be removable, and the crankpins P, 



Fig. 122 

Top View Russel’s Ring 

if they fit the slots Id in one position, must fit 
them in any position which the cranks occupy. 
It is also clear that since the device is symmetri¬ 
cal that the cranks B if they move at all must 
have equal and opposite movement. Assume 
the cage C to be stationary and the right-hand 



256 


The Automobile Handbook 


crank B to turn towards the top, in direction 
of arrow X; this will tilt the ring out of its 
horizontal plane, and the opposite side of the 
ring will push the left crank B down in direc¬ 
tion of the arrow Y, through the same angle as 
the right crank B took. This shows there is a 


Fig. 123 

Vertical Section of Russel’s Ring 

perfect differential. It will be seen that when 
these cranks B have turned 90 degrees in the 
opposite direction, the ring D will be vertical 
in the illustration and a dead center will be the 
result. This has been overcome, as illustrated 
in Fig. 121, by using two rings D and D 1 , the 













The Automobile Handbook 


257 


latter inside of the former. This illustration 
shows the complete device, except that the dot¬ 
ted lines merely indicate the general position 
that will be occupied by the rings D and D 1 , 
which are held separate by washers W. Fig. 
122 shows a top view of the ring D and it will 
be seen that the slots H, instead of being par¬ 
allel to the axis of the oscillation of the ring 
are turned to an angle of 30 degrees of this 
axis; the effect of this is to make the dead cen¬ 
ter occur when the cranks are 90 degrees apart 
instead of when they are 180, as shown in Fig. 
120. Fig. 123 is a cross section of the rings D 
and D 1 and shows the relative position of the 
slots H in the two rings. It will be seen that 
these slots in one ring are placed somewhat like 
the threads on a double thread right-handed 
screw, while those in the other ring are placed 
like the threads on a left-handed screw. The 
effect of this is to make the dead centers of 
the two systems come 90 degrees apart, and so 
produce continuous rotation. 

There are still other forms of differentials, 
but these are the simplest and most common of 
the type that, while positively controlling the 
wheels of the vehicle, send half the power to 
each at all times regardless of their respective 
movements. 

Testing Differential Gears. The differen¬ 
tial gear should be tested with a view to locat¬ 
ing any wear or side play. This may be done 
by jacking up the rear axle and shaking one 


2 58 


The Automobile Handbook 


wheel forward and backward while the other 
is held stationary, and noting how far the 
wheel must be turned before the movement is 
taken up by the flywheel of the engine. Any 
noticeable play will generally be found either 
in the center pinions of studs of the differential 
gear, in the large and small bevel gears, in the 
clutch sleeve, or in the universal joints. The 
differential gear, and live axle of modern cars 
seldom give trouble if kept properly lubricated, 
and the car’s mileage should run up into many 
thousands before any considerable amount of 
play is evident. The joint pins of the propeller 
shaft may become loose through wear, in which 
case a knocking noise in the transmission gear 
will indicate the cause and locat/ion of the 
trouble. These pins may be readily replaced 
with new ones at small cost. If the play is 
found in the bevel gears, the small gear should 
be adjusted to mesh deeper with its larger mate. 
This may be done by means of the adjustable 
locking ring or by inserting a washer of the 
proper thickness. It may be found, however, 
that no adjustment is necessary, and a thor¬ 
ough cleaning with gasoline to remove all oil 
and grease will be all that is required. The 
case should then be refilled with the quantity 
of oil and grease recommended by the manu¬ 
facturers. 

Distributers. Instead of employing a sepa¬ 
rate spark coil for each cylinder of a multi- 
cylinder engine, the primary circuits of which 


The Automobile Handbook 


259 


are made and interrupted in rotation, a device 
known as the distributer may be used, which 
permits of any number of cylinders being 
sparked from a single coil. In magnetos de¬ 
signed for jump spark ignition of multi-cylin¬ 
der engines the distributer forms part of the 
magneto and is rotated by it. The distributer 
is nothing more than a timer of secondary cur¬ 
rent, and generally consists of a cylindrical shell 
of instating material, upon the inside of the 
cylindrical surface of which equidistant metal¬ 
lic segments in number equal to the motor cyl¬ 
inders are inserted. A conducting arm rotat¬ 
ing upon a shaft concentric with the insulated 
shell carries a brush, which successively makes 
contact with the segments. The arm is in per¬ 
manent electrical connection with the free sec¬ 
ondary terminal of the coil, and each one of 
the segments is wired to the spark plug of a 
cylinder. 

In the case of four-cylinder motors the 
moving arm is geared at one-half the speed of 
the motor, thus making contact for each cyl¬ 
inder once in each two revolutions or complete 
cycle. 

Don’ts. In the first place don’t forget to as¬ 
certain the fact that the ignition mechanism is 
retarded before cranking the motor. Many a 
sprained wrist and not a few cases of broken 
heads or arms’have been caused by the neglect, 
of this simple precaution. It is a good plan to 


260 


The Automobile Handbook 


have the ignition-control spring so actuated that 
in its normal position it is always retarded. 

If the motor should not happen to start the 
first time, don’t forget to keep out of the way 
of the crank when the motor is stopping. It 
might take a turn backwards and take the 
crank with it. 

Don’t forget to close the battery switch be¬ 
fore starting the motor. 

Don’t allow the motor to stand in such a 
position that with the battery connected, the 
vibrator of the spark coil will work. It is al¬ 
most the same as a short-circuit, and will run 
down the battery rapidly. 

Don’t use a match or a small torch to inspect 
the carbureter. It sometimes leads to unex¬ 
pected results. 

Don’t forget to fill the gasoline tank before 
starting. 

Don’t smoke while filling the gasoline tank. 

Don’t take out all the spark plugs when 
there is nothing the matter, except that there 
is no gasoline in the tank. 

Don’t forget to always have an extra spark 
plug on the car. 

Don’t allow the motor to race or run fast 
when out of gear. If the car is to be stopped 
for a few minutes, without stopping the motor, 
retard the ignition and also throttle the charge, 
so that the motor will run as slowly as possible. 

Don’t fill the gasoline tank too full, leave an 


The Automobile Handbook 


261 


air space at the top or the gasoline will not flow 
readily. 

Don’t have any open hole in the gasoline 
tank. When the car is washed water may run 
in this hole, mix with the gasoline and cause 
trouble. 

Don’t put grease in the crank case of the 
motor, it will clog up the oil holes and prevent 
the oil from circulating. 

Don’t fill the gasoline tank by lamp or candle 
light, something unexpected may happen. 

Don’t keep on running when an unusual noise 
is heard about the car, stop and find out what 
it is. 

Don’t start or stop too suddenly, something 
may break. 

Don’t pour gasoline over the hands and then 
rub them together. That rubs the dirt into the 
skin. The proper way to do is to saturate a 
towel with gasoline and then wipe the dirt off. 

Don’t forget to examine the steering gear 
frequently. 

Don’t fail to examine the pipe between the 
carbureter and the admission-valve occasionally. 
The pipe connections sometimes get loose and 
allow air to enter and weaken the mixture. 

Don’t forget to see that there is plenty of 
water and gasoline in the tanks. 

Don’t fail to clean the motor and all the 
wearing parts of the car occasionally. 

Don’t forget to oil every part of the motor 


262 The Automobile Handbook 

where there is any friction, except the valve 
stems. 

Don’t spill gasoline on the clothing and then 
strike a match to light a pipe, some one may be 
sorry afterwards. 

Don’t go out for a run without a complete 
equipment of tools, extra parts, gasoline, and 
tire repair outfit, or a late return may be ex¬ 
pected. 

Don’t let a willing bystander fill up the gaso¬ 
line tank with water. 

Don’t leave the water in the circulating sys¬ 
tem on a frosty night, except with 40 per cent 
of gylcerine in it, and never when below zero. 

Don’t start away with the brake on and 
wonder why the motor is not working well and 
in conclusion, 

Don’t let the starting handle fly off and hit 
somebody on the chin. 

Driving—General Rules for. When on the 
open road, away from cities or towns, the fol¬ 
lowing rules should be borne in mind. (1) 
Drive with moderate speed on the level, slow 
speed down hill, and wide open throttle for 
hill climbing, or getting up speed only. (2) 
The condition of the road should be noticed, 
the presence of mud or dust thereon furnishing 
sufficient reason for slowing down somewhat 
for the sake of other road users. (3) The or¬ 
dinary rules of the road regarding the negotia¬ 
tion of turns, and crossings, also the overtak¬ 
ing or passing of other vehicles should be ad- 


The Automobile Handbook 


263 


herecl to, even though a lower rate of speed is 
involved thereby. (4) A sharp lookout should 
always be kept for traffic of all kinds, as well 
as on approaching schools, churches, or public 
buildings, and also for road signs indicating 
danger, caution, # etc. (5) When on the road 
the autoist should show courtesy to other road 
users. Courtesy in autoists is much apprecn 
ated, and goes a long way toward removing 
the prejudice which exists in many places 
against automobiles. 

Driving-wheels, Large versus Small. The 

larger the wheels, the less power should be re¬ 
quired to drive a car. Theory shows that the 
road resistance decreases in proportion as the 
wheel diameter gets larger. The result of ex¬ 
periments to verify this do not show quite such 
favorable results, but a gain almost in propor¬ 
tion to the square root of the wheel diameter 
has been obtained. The principal reasons why 
large wheels are not more used are as follows: 

The center of gravity of the car is raised and 
makes the car less stable in turning corners. 
They are more expensive and more liable to 
injury than wheels of smaller diameter. They 
increase the cost of the tires enormously. They 
make access to the seats more difficult on ac¬ 
count of the increased height of the car. 

Dynamometer. A dynamometer is a form of 
equalizing gear which is attached between a 
source of power and a piece of machinery when 
it is desired to ascertain the power necessary 


264 


The Automobile Handbook 


to operate the aforesaid machinery with a given 
rate of speed. 

E. C. B. Carbureter. Fig. 124 shows a sec¬ 
tional view of the E. C. B. carbureter in which 
there are three air inlets. A is the normal in¬ 
let, in which the air current is. converged at the 
nozzle. C and D are two openings, each hav¬ 
ing a sliding throttle for purposes of regulation. 
C is for cold air, D is for heated air, and the 



Fig. 124 

E. C. B. Carbureter 


valve controlling these openings may be set 
for a maximum of cold air, and a minimum of 
heated air. or vice versa, according to the tem¬ 
perature of the atmosphere. The engine con¬ 
nection B is ordinarily supplied without a 
throttle, although, if desired, a throttle K is 
furnished. The main feature is to control the 
entering air, rather than the mixture passing to 
the engine. In addition to its threefold inlet, 
this carbureter has two spraying nozzles. The 










































The Automobile Handbook 


265 


small one N, always open, and just large enough 
to keep the motor in motion when running idle, 
and the larger one M, which is controlled by 
needle valve H, which is raised and lowered as 
the air entrances are varied. G is a conical 
wire screen, the purpose of which is to prevent 
back firing. The openings of nozzles INI and N 
are both well above the bottom of the float 
chamber. 

Gasoline enters by connection E, being con¬ 
trolled by a needle valve operated by float F. 
The level of the gasoline is visible through the 
glass portion of the casing, which is marked 
with graduations. The float level is adjustable 
by loosening lock nut Z, which holds cone over 
X, which latter acts as a guide for the stem of 
the needle valve. Guide X rests in a series of 
slots, and by raising it out of one slot, and 
turning it through part of a revolution until in 
position to drop into another slot, the level of 
the gasoline is changed. 

Economy Carbureter. This carbureter has 
two spraying nozzles, N, N, Fig. 125, located 
side by side, the tip of one extending into a 
strangling tube of much larger capacity, the 
outlet of which is controlled by a flap valve F, 
that remains closed when the machine is run¬ 
ning light, but when the demand for fuel in¬ 
creases, this valve opens, and both nozzles fur¬ 
nish the supply. In other ways this carbureter 
follows the usual construction. 

Efficiency of a Gasoline Motor. In text- 


266 


The Automobile Handbook 


books the efficiency of a motor is usually con¬ 
sidered as the relation between the heat-units 
consumed by the motor and the work or energy 
in foot-pounds given out by it. If the heat- 
units (which are measured by the quantity of 
fuel supplied to the motor) be large compared 
to the work or energy given out by the motor, 
its efficiency is small. 

At the present time the quantity of liquid 
fuel consumed by an explosive motor for auto¬ 



mobile use is of secondary importance. The 
fuel economy of a motor is important, but it 
does not usually occupy the first place in auto¬ 
mobile construction. The consideration of pri¬ 
mary importance is to obtain the maximum 
amount of power from a motor of minimum 
weight. As only about one-fifth of the heat- 
units consumed by an explosive motor are 
utilized, or given up in the form of work or 
energy, there is consequently room for great 
improvement. 































The Automobile Handbook 


267 


The power for weight efficiency of a motor 
increases almost in proportion to the speed 
with high speed explosive motors, but the fuel 
efficiency of a motor decreases with the speed 
beyond certain limitations. 

Electricity, Forms of. Electricity or electri¬ 
cal energy may be generated in several ways— 
mechanically, chemically and statically or by 
friction. By whatever means it is produced, 
there are many properties which are common 
to all. There are also distinctive properties. 
The current supplied by the storage battery 
will flow continuously until the battery is prac¬ 
tically exhausted, while the current from a dry 
battery can only be used intermittently; that is, 
it must have slight periods of rest, no matter 
how short they may be. 

The dynamo or magneto current is primarily 
of an alternating nature, or one which reverses 
its direction of flow rapidly. In use, this alter¬ 
nating current is changed into a direct or con¬ 
tinuous current flowing in one direction only, 
by means of a commutator. Any of the forms 
described are capable of igniting an explosive 
charge in a motor cylinder, but the static or 
frictional form of electricity is not used for this 
purpose on account of its erratic nature. 

Electric Apparatus—Care of. The following 
instructions apply particularly to electric ap¬ 
paratus in connection with the operation of au¬ 
tomobiles. Look over the electrical plant and 
replace worn wires with new. Clean out the 


268 


The Automobile Handbook 


timer with gasoline and lubricate with light oil. 
The magneto need not be taken apart, as it will 
probably only need a little surface cleaning, a 
few drops of oil, and the amateur had better 
not meddle with its internal mechanism. The 
storage battery should be examined, and if the 
brown deposit collects in any quantity at the 
bottom, the electrolyte should be poured out 
into a glass bottle, and the battery washed out 
with clear water (rain water preferred). Clean 
the top of the battery and make it a point to 
keep it clean and free from acid. Clean the 
terminals of any corrosion, and see that the air 
vents are not clogged up. If the accumulator 
has been .neglected, either in the electrolyte 
having been allowed to get below the proper 
level or in not giving it the regular monthly 
“charge,” it may get a bad case of sulphating. 

To get the battery into its normal condition, 
empty out the electrolyte and wash the case 
thoroughly with soft water. Pour in only 
about seven-eighths of the acid solution and fill 
up with distilled water to cover the top of the 
plates. The battery should then be charged 
with a low current until the plates are restored 
to their normal condition. If very badly sul- 
phated, the white coating should be washed off 
with a rag, and in case this fails to remove it, 
scraping must be resorted to. If the electro¬ 
lyte is not sufficient to cover the top of the 
plates, fill up with distilled water so that the 
liquid will just cover them. The specific grav- 


The Automobile Handbook 


269 


ity of the electrolyte should not be less than 
1.150, and, although varying somewhat, a hy¬ 
drometer reading of 1.250 is recommended. 
This is approximately 1 part of sulphuric acid 
to 4% parts of water, which will be found suf¬ 
ficiently accurate if no hydrometer is at hand. 
If the electrolyte should test lower than the 
first figure, add pure sulphuric acid until the 
1.250 mark is reached. 

In case the plates are broken down or 
“buckled,” or if the paste has dropped out of 
the pockets of the grids, the accumulator should 
be sent to the manufacturers for repair. In 
some accumulators the liquid is not used, but a 
jelly made of silicate of sodium and dilute 
sulphuric acid takes its place. If your battery 
is of this type, it is well to remember that the 
jelly must be kept moist on the top, and as the 
emulsion becomes dry a little water .should be 
added to replace that which is lost through 
evaporation. 

The contact points of the coil will probably 
require adjusting. This is very easily accom¬ 
plished by trimming up the points with emery 
paper. Do not rub away the metal unneces¬ 
sarily, only removing enough to true the points 
so that they make a good contact. In adjust¬ 
ing the vibrator, remember that a light tension 
is much better than a stiff tension. A light 
flexible vibration with a moderately high- 
pitched buzzing note will not only give a better 
spark, but will keep the points in better shape. 


270 


The Automobile Handbook 


A heavy tension will make the coil less respon¬ 
sive and will pit the contact points and exhaust 
the battery more quickly. As a coil will ren¬ 
der the most efficient service only when the vi¬ 
brators are adjusted as nearly alike as possible, 
a special ammeter is often used to determine 
the current consumption of each unit. The am¬ 
meter should show a reading of 6-10 amperes. 

Electric Lamps. It is well to remember that 
electric lamps consume a great deal of power. 
One 16 candlepoAver lamp requires about one- 
twelfth of a horsepower to operate it. The 
electrical energy required per candlepower is 
a trifle over 4 watts. A 4-volt, 4 candlepower 
lamp would require a storage battery of 24 
ampere-hour capacity to enable the lamp to 
burn 6 hours. The same battery would run a 
4-volt, 1 candlepower lamp 24 hours. 

Electric Motors. A well designed electric 
motor for use in connection with a storage bat¬ 
tery for automobile propulsion must be capable 
of withstanding an overload of over 100 per 
cent for at least thirty minutes at a time, or for 
even a longer period, without unduly over¬ 
heating. The motors used on electric automo¬ 
biles are usually series-wound, as this type of 
winding has been found to give the most satis¬ 
factory results in general use. 

There are three types of electric motors in 
general use, these are: 

Shunt-wound motors, in which the field-mag¬ 
nets are wound with a great many turns of 


The Automobile Handbook 


271 


very small wire, the ends of which are directiv 
connected to the terminals of the commutator 
brushes. 

Series-wound motors, which have the field- 
magnets wound with a few turns of very large 
wire. One end of this wire is connected to 
one commutator brush terminal. The other end 
of the wire on the field-coils, and the other brush 
terminal being* connected with a battery or 
other source of current. 

Compound-wound motors are a combination 
of the above motors, having* the field-magnets 
double-wound, that is with both shunt and 
series-windings. 

The armature of an electric motor is built up 
of a number of disks of sheet iron, which are 
separated from each other by a suitable coating 
of varnish or by the use of thin sheets of paper 
between the disks, this is to prevent what are 
known as eddy currents, which are a source of 
constant trouble if not eliminated. 

The function of the commutator of an electric 
motor is to receive the current from the batt.erv 
or other source of power, by means of the 
brushes, and transmit it to the windings or 
coils upon the periphery of the armature. 

The essential features of an electric motor 
are as follows: 

The brushes, which are located upon and 
around the periphery of the commutator and 
serve to transmit the current to the commutator 
from the outside source of supply. 



ELECTRIC MOTOR 


















































































































































The Automobile Handbook 


The commutator or current distributor, and 
laminated wrought iron armature. 

The field-magnets and pole-pieces; the lat¬ 
ter are usually an extension of the magnet core. 

The magnet frame, usually of cast steel. 

Figure 126 shows a form of series-wound 
electric motor of the style most commonly used 
for automobile work. The motor is of the four- 
pole type, having its field-coils arranged at 
equi-distant points around the periphery or cir¬ 
cumference of the armature. The armature 
shaft is carried by ball bearings, with suitable 
screw and clamp adjustment as shown. The 
armature is of the slot-wound type and has a 
commutator with self-adjusting carbon brushes. 
The left-hand extension of the armature shaft 
is fitted with a key and washer for the driving 
gear or sprocket, while the right-hand end has 
a pulley or brake wheel to use for stopping the 
car under ordinary conditions of travel. The 
magnet frame is of cast steel, and the magnet 
cores and armature disks of laminated wrought 
iron. The field-coils are machine-wound, and 
the armature coils form-wound, while both are 
thoroughly taped and waterproofed. The com¬ 
mutator generally has the same number of sec¬ 
tions as the armature has slots and is usually 
of large diameter and wide contact face. 

Electric Motor Troubles. Electric motor 
troubles may be classed as follows: Open- 
circuits, improper connections and short-cir¬ 
cuits. 


274 


The Automobile Handbook 


An Open-circuit may be found at any one of 
the following- places: 

Battery terminals. These may be badly cor¬ 
roded or worked loose, so as to form a poor or 
improper electrical contact. 

Controller. A connection may have worked 
loose, or the spring contact-fingers are not mak¬ 
ing good contacts. 

The removable plug may be out or not male, 
ing a proper contact. 

Brushes. One of the carbon brushes of the 
motor may have fallen out, or the brush springs 
may be too weak to insure a good contact. 

The reversing switch may be halfway over, 
thus leaving the batteries and motor on an 
open circuit. 

All points of contact, such as terminals or 
binding-posts, brush-holders, switches and con¬ 
troller spring contact-fingers, should be bright 
and clean so as to give a perfect metal-to-metal 
contact. 

The fact that the car will not start and the 
ammeter shows no current indication is gener¬ 
ally an indication of improper battery connec¬ 
tions. 

When the different trays of the battery are 
not properly connected together, short-circuits 
will occur between these sections and run down 
or exhaust the batteries in a very short time. 
All battery terminals should be plainly marked 
so that it is impossible to make wrong connec¬ 
tions. If the trouble above stated occurs the 


The Automobile Handbook 


275 


battery trays must be wrongly connected 
amongst themselves. 

Tf the ammeter indicates a large current and 
the motor refuses to turn, the trouble is what is 
known as a short-circuit, or a path for the 
current outside of the motor. 

Lift one of the commutator brushes, and if 
the amperage shown by the ammeter drops, or 
perhaps disappears altogether, one of the field- 
coils is short-circuited or there is a broken wire 
touching some part of the metal of the car or 
an exposed portion of another wire. 

Electric Motors, Speed-Regulation of. The 
speed and consequently the power of an electric 
motor may be varied in three ways, as follows: 

First, by introducing variable resistances in 
the motor and battery circuit. 

Second, by varying the voltage of the bat¬ 
teries by different combination of the battery 

travs. 

«/ 

Thirdly, by connecting the field-coils of the 
motor; all in series, in series-parallel and all in 
parallel. Various other combinations of the 
above named methods may also be had. 

Electrical Horsepower. One electrical horse¬ 
power is equal to the current in amperes multi¬ 
plied by the electro-motive force or voltage of 
tin* circuit and divided by 746. 

Let C be the current in amperes and E the 
voltage of the circuit. If E. II. P. be the re¬ 
quired electrical horsepower, then 


276 


The Automobile Handbook 


EXC 

E.H.P=- 

746 

In practice with motors of small power, 1,000 
watts are necessary to deliver one mechanical 
or brake horsepower at the driving shaft of the 
motor. 

If the actual or brake horsepower of an elec¬ 
tric motor be known, the efficiency of the motor 
may be readily found by the following formula : 

If E be the voltage of the circuit and C the 
current in amperes consumed by the motor, let 
B. II. P be the brake horsepower of the motor 
and e the efficiency of the motor, then 

B.H.P X 746 

e —- 

EXC 

Table 10 gives the electrical horsepower of 
motors with voltage from 20 to 100 volts, and 
current strengths from 10 to 80 amperes. 

The mechanical efficiency of a motor may be 
found by use of the table as follows 

Example: Required the mechanical efficiency 
of a 40-volt, 60-ampere motor, which is rated 
by its maker as of 3.25 horsepower—the motor 
when under full load using 80 amperes. 

Answer: Reference to the column in the table 
corresponding to 40 volts and 60 amperes gives 
3.22, while the 80 ampere column gives 4.29. 
Tlu'n 3.22 divided by 4.29 gives 0.75, or 75 per 
cent, as the mechanical efficiency of the motor. 




The Automobile Handbook 


277 


TABLE 10. 

ELECTRICAL HORSEPOWER OF MOTORS. 


<u 

bfl 

Current in Amperes. 

o 

, 

10 

20 

1 1 J 

30 | 40 | 50 

60 

70 

80 

K' 



1 1 


! 


20 

.29 

.54 

.79 | 1.07 | 1.34 

1.61 

1.88 

2.14 

40 

.54 

1.07 

1.61 | 2.14 | 2.68 

3.22 

3.75 

4.29 

GO 

.79 

1.61 

2.41 | 3.22 | 4.02 

4.82 

5.56 

6.43 

80 

1.07 

2.14 

3.22 | 4.29 | 5.36 

| 6.43 

7.50 

8.58 

100 

1.34 

2.68 

4.02 | 5.36 | 6.70 

7.94 

9.38 

10.72 


Electro-magnetic VibRx\tor. Gasoline mo¬ 
tors with high compression and speed require a 
jump-spark of greater intensity and volume 
than those with less compression and speed, to 
properly ignite the charge. They consequently 
require a battery of higher voltage and greater 
current volume to induce a greater flow of the 
magnetic flux or lines of force in the iron core 
of the coil. This has the effect of reducing the 
number of vibrations per minute of the trem¬ 
bler attached to the coil. Numerous tests have 
shown that when the motor to which such a 
coil is attached, attains a certain rate of speed, 
the vibrator refuses to work when the circuit 
it closed by the commutator on the motor. 
That is due to the fact that the period of time 
during which the electrical circuit is closed and 
opened by the commutator is not of sufficient 
duration to allow the vibrator to properly per¬ 
form its function. It is to overcome these ob¬ 
jections that the electro-magnetic vibrator, here 
illustrated and described, is intended. 

Figure 127 is a plan or top view, clearly show¬ 
ing the wiring and connections to the terminals 















278 


The Automobile Handbook 


or binding-posts. This is also an important 
point in the construction, and enables the oper¬ 
ator to connect the vibrator to the coil, battery 
and motor without any chart or previous in¬ 
structions, and if properly connected as marked, 
no ground or short-circuit can occur. P and P 
are the connections to the primary winding of 
the induction coil; B and B, the battery con¬ 
nections, and C and C the connections to the 



Fig. 127 


commutator on the motor. The wiring shown 
by the dotted lines between the terminals P 
and B, and also between P and C, are merely 
blind or dummy wires, so as to prevent anv 
mistakes in the wiring of the car, as all con¬ 
nections between the battery, coil and motor 
must be made through the vibrator. As this 
electro-magnetic vibrator is not connected in 
series with the battery and coil current, but is 
in a simple shunt from the battery, it utilizes 

























































The Automobile Handbook 


279 


only a fraction of the battery current, while the 
remainder of the current goes directly to the 
primary winding of the coil, and the current 
used by the coil is at all times controlled by the 
operation of the vibrator. 

The trouble experienced by owners of cars 

having multi-cylinder motors equipped with 

the ordinary vibrator or trembler form of 
%/ 

jump-spark ignition indicates that something 
more reliable, more nearly fool proof, and 
therefore better adapted to the requirements 
of the automobile maker and user, is required. 
The use of this device insures the absolute syn¬ 
chronization or timing of the spark in multi- 
cylinder motors with any number of cylinders. 

Electro-motive Force, Definition of. The 

cause of a manifestation of energy is force; if 
it be electric energy in current form it is called 
electro-motive force. An electro-motive force 
or pressure of one volt will force one ampere 
through one ohm of resistance. 

Engine—Requirements of. An automobile 
engine should answer the following require¬ 
ments in order to meet the demands of the mo¬ 
tor user: It must be of light weight in propor¬ 
tion to its horse power, so that as large a pro¬ 
portion of its power as possible may be avail¬ 
able for propelling the useful load, and but lit¬ 
tle demanded to move its own weight; it must 
be compact, in order that it shall not occupy 
too large a proportion of the available room of 
the car; it must operate without undue noise 


280 


The Automobile Handbook 


and vibration; it must be fully enclosed as a 
protection against the weather, and still it must 
be so located as to be easily accessible for in¬ 
spection, oiling and repairs; its operation must 
be automatic for considerable periods of time, 
as regards cooling and lubrication; it must be 
capable of running very slowly, or very fast at 
will, and of developing little, or much power; it 
must be supported upon the car in such a man¬ 
ner that its power may be most readily and 
efficiently transmitted to the driving wheels, 
and it must further be carried upon springs so 
that the jar and shock from the road shall not 
be transmitted to it. 

Exhaust—Cause of Smoky. Smoke coming 
from the exhaust of a gasoline motor is due to 
one of two conditions: Over-lubrication—too 
much lubricating oil being fed to the cylinder of 
the motor- or too rich a mixture, that is, too 
much gasoline and an insufficient supply of air. 

The first condition may be readily detected 
by the smell of burned oil and a yellowish 
smoke. The second, by a dense white smoke 
accompanied by a pungent odor. 

Exhaust Muffler. When the exhaust gases of 
an explosive motor are allowed to pass out 
through the exhaust pipe directly into the at¬ 
mosphere, the sharp explosions rapidly suc¬ 
ceeding each other are very annoying, and it 
is for this reason that the device termed an 
exhaust muffler is, or at least should be, used. 
Various types of mufflers are in use, each no 


The Automobile Handbook 


281 


doubt possessing its own particular merit. The 
function of the muffler is to deaden the noise of 
the escaping gases, and the general require¬ 
ments of the device are as follows: (1) It must 
be built strong enough to withstand the force 
of any explosion liable to occur within it. due 
to the escape of an unexploded charge, which 
may take place in one of the engine cylinders. 
(2) It must check the velocity of the escaping 
gases without causing too much back pressure 
on the motor. (3) It must deaden the noise. 




1 = 



l 


i 


MUFFLER 


Fig. 128 

The last two requirements may be attained by: 
(a) Breaking up the gases into a number of 
fine streams: (b) Allowing the gases to expand 
and cool; (c) Reducing the pressure of the 
gases, until they are as nearly as possible at 
atmospheric pressure. 

The terminal or exhaust pressure ranges at 
from 30 to 50 pounds per sq. in. above atmos¬ 
pheric pressure, while the temperature will be 
800 to 1100 degrees F. 

Figure 128 illustrates a form of muffler with 














282 


The Automobile Handbook 


a central inlet-pipe, provided with slotted open¬ 
ings as shown. The chamber is divided into 
two parts by a plate, in and around which are 
located a number of small tubes for the passage 



Fig. 129 

Concentric Muffler Used on the Studebaker Cars 


of the gases. A similar set of tubes are lo¬ 
cated in the discharge end of the muffler. 

Figs. 129, 130 and 131 show sectional views 
of different forms of the type of exhaust muf 
her known as the concentric type. The muffler 
shown in Fig. 129 consists of two or more cyl- 



Fig. 130 

Concentric Muffler with Cut-Out 


inders closed at both ends, there being an en¬ 
trance into one of them from the exhaust pipe, 
and an exit from another into the atmosphere, 
while the exhaust gases pass from cylinder to 

































































The Automobile Handbook 


283 


cylinder by means of small holes, which serve 
to break up the gas into small streams. In Fig. 
130 the path of the gas is shown by the arrows. 
It enters the inner cylinder, and its impact is 
cushioned by the air therein. Returning it 
passes through a series of small holes into the 
next larger cylinder. Continuing to expand 
and cool in this manner, it finally reaches the 
outer cylinder, from which it passes through 
another series of holes into the collector cham¬ 



ber A, and from thence it flows out through the 
tube at the bottom. This tube being located at 
one side, the gas coming from the different holes 
B, B has a different length of path from each to 
the tube, consequently the discharge from holes 
B, B begins simultaneously, and the discharge 
from the outlet is gradual. 

The Friedman exhaust box (Fig. 131) is an 
interesting device. A number of concentric 
tubes or drums communicate with one another 
through the perforations indicated. The ex- 
































284 


The Automobile Handbook 


liaust enters from each cylinder at oppose 
ends of the central tube, from which it diffuses 
outwards. As the exhaust gases from the two 
cylinders oppose one another in the inner tube, 
the noise is almost completely silenced. The 
exhaust finally escapes through holes in the 
outside drum. 

Fig. 132 shows a sectional view of the Olds- 
mobile exhaust silencer, in which the exhaust 
gases enter the free space, and percolate slowly 
to the outer air through the two bent pipes 



which are perforated near the ends. The am¬ 
ple size, and the gradual passage of the gases 
account for its efficiency. The Prestwich-Drury 
exhaust muffler is a cylinder A, Fig. 133, with 
removable ends. The closed tubes C, D and E, 
are shorter than the cylinder so that a space 
0 is left between their ends and those of the 
cylinder. These tubes are shaped to accommo¬ 
date themselves to that of the cylinder, and 
they create passages (J, K, L) extending lon¬ 
gitudinally. The exhaust gases are admitted 
near the center of the cylinder as at H, into 

























The Automobile Handbook 


285 


one of the tubes and pass out through holes neaf 
one end communicating with the adjoining tube, 
which has holes communicating with the third 
tube. This has a number of small holes (F) 



communicating with one of the passages (L). 
After circulating in the outer passages, the now 
greatly expanded gases pass to the atmosphere 
through a pipe M, fitted near one, or both ends 
of cylinder A. Fig. 133 shows a longitudinal 


















































( 


286 The Automobile Handbook 

and cross section of the device. The Wain- 
wright exhaust silencer, Fig. 134, is a compara¬ 
tively elaborate device. The gases pass from 
the motor through pipe A which branches into 
B and C. Between the ends of B and C is a 
chamber D. the dimensions of which vary ac- 
cording to requirements. This chamber is of 
double-conical form, the flanges at their bases 



Fig. 134 

Wainwriglit Exhaust Silencer 


being secured together by bolts or screws K. 
The bases E of the conical chambers have holes 
M, and inside the chamber D are a number of 
plates F, the conical perforations (G) in which 
are larger in diameter at the exit side. These 
perforated plates are supported on central bolts 
(IT), whose external ends are preferably 
screwed into the end plates. The plates are 
kept the required distance apart by means of 







































The Automobile Handbook 


distance pieces or washers J. Another means 
of supporting the internal baffles may be 
adopted if desired. The exhaust gases flow 
through the pipes A, B, and C through the per¬ 
forations in the plates F, and out through the 
perforations M in the chamber D to the atmos¬ 
phere. In doing so the gases become broken 
up. The rain shields L, secured by bolts K, 
do not obstruct the passage of the gases, which 
pass through them in the direction indicated 
by the arrows. 



Fig. 135 shows a longitudinal section of the 
ejector type of muffler, in which the flow of gas 
through a nozzle creates a vacuum in the cham¬ 
ber surrounding it. The vacuum space is 
filled by gas, shunted from the stream that sup¬ 
plies it to the nozzle, and this shunted gas 
passes through crooked passages before it 
reaches the nozzle chamber. There are three 
expansion chambers, which are formed by con¬ 
ical diaphragms perforated on top and bot¬ 
tom alternately. There is an axial tube lead¬ 
ing through the device, which is of varying 


























288 


The Automobile Handbook 


diameter, and part of the gas entering the muf¬ 
fler passes directly from the axial tube into the 
center chamber and through the second set of 
cones before the gas which enters the first- 
chamber has passed through the first set. A 
portion of the gas is conducted straight through 
to the nozzle, and hence to the atmosphere, its 
discharge creating a partial vacuum in the third 
chamber, developing a suction, which draws the 
gas out of the third chamber in a uniform 
stream. 



The muffling effect is obtained by drawing 
the gas off in a uniform stream and reducing the 
pressure before the main body of the gas en¬ 
ters the atmosphere. The pressure in the first 
chamber is higher than that in the second 
chamber, and the third chamber has a pressure 
slightly above that of the atmosphere. In this 
type of muffler the whole of the exhaust gas will 
pass out before the next exhaust, leaving the 
pressure in the muffler slightly below that of 
the atmosphere. The set of cones nearest the 
outlet prevents the air from rushing in and fill- 



























The Automobile Handbook 


289 


mg' the muffler, avoiding the necessity of driv¬ 
ing the air out ahead of the next exhaust. Thus 
the exhaust expands in a chamber below at¬ 
mospheric pressure. 

Radiating Fin Muffler. -In a few instances 
the radiating fin muffler has been used. In this 
type, shoAvn in Fig. 136, the muffler consists of 
a pipe, larger than the exhaust pipe leading 
from the engine, on which are placed a number 
of truncated cones or saucer-shape discs of 
metal. The gas escapes from the pipe through 
holes in the disc, thence into the atmosphere by 
forcing the edges of the discs apart. The pres¬ 
sure of the gas left in the engine, cylinder, ex¬ 
haust pipe and muffler will depend on the 
amount of pressure necessary to force the discs 
open. They are generally made of copper, 
which has the advantage of being a good con¬ 
ductor of heat. 

Muffler Exits. The final passage of the ex¬ 
haust from the muffler into the air is accom¬ 
plished in a number of ways; most mufflers use 
a tube, sometimes the end of the tube is full 
size, sometimes it is made smaller but still left 
round, sometimes it is flattened. In any case, 
this outlet should be so located that as the 
charge passes through the muffler it reaches the 
outlet slowly and in a nearly continuous stream. 

Muffler Cut-Outs. Mufflers are generally 
equipped with muffler cut-outs, which by-pass 
the gas so that it exhausts direct into the at¬ 
mosphere with its attendant noise. There are 


290 


The Automobile Handbook 


three reasons why they are so equipped, namely: 
to tell if the engine is exploding regularly; to 
clean the exhaust pipe; to have it act as a safety 
valve in case of explosions in the muffler. If the 
power of the engine increases when the muffler 
is cut out, it is a sure sign that the muffler is of 
defective design or needs cleaning. 

Muffler Cut-Out Valve. One form of cut¬ 
out valve is shown in Fig. 137. It is inserted 
in exhaust pipe P, by sawing a hole in its under 



side. The cut-out valve housing clamps to the 
pipe by a couple of V-clamps. The valve is 
carried in a cylindrical compartment under the 
exhaust pipe, and consists of a spring closed 
poppet valve a little larger in diameter than the 
internal diameter of the exhaust pipe. It opens 
against the exhaust pressure to prevent leakage. 

Care of Mufflers. From time to time, all 
mufflers should be cleaned, because it will be 
found that they will contain a considerable 
amount of carbon deposits. These deposits not 






















The Automobile Handbook 


291 


only tend to increase the back pressure, but 
they retain the heat of the exhaust, thus al¬ 
lowing the gases to escape at a higher tempera¬ 
ture than they should. A muffler should be 
taken apart and cleaned once a year, or oftener 
if there are any indications of loss of power, 
resultant from back pressure. 

Exhaust-valves, Diameter and Lift of. The 
formulas, and Table No. 1, given for admission- 
valves, apply also to exhaust-valves. For mo¬ 
tors with excessively high speed, the valve 
diameter given by the formula or table should 
be increased at least 15 per cent, the formula 
will then read, 

B X S X R 

D =-- 

13,000 

where D is the required diameter of the valve 
opening, B the bore of the cylinder, S the 
stroke of the piston and R the number of revo¬ 
lutions per minute of the motor. 

Exhaust Valve Closure. Some of the loss in 
efficiency of a gas engine may be caused by the 
improper closing of the exhaust valve. If it 
closes too early, an excess of burned gas will 
remain in the cylinder, while if it is kept open 
too long some of the burned gas will re-enter 
the cylinder during the suction stroke. If the 
exhaust valve area were as large, or nearly as 
large, as that of the cylinder, there would be 
no appreciable back pressure, and in this case 
the exhaust valve would not have xo be opened 



292 


The Automobile Handbook 


before the end of the stroke. Since, however, 
all exhaust passages are restricted in area, the 
exhaust should be so timed that the loss re¬ 
sulting from an early opening, and the loss 
arising from too much back pressure should 
be a minimum. 

Expansion—Best Conditions for. The effi¬ 
ciency of the expansion in an engine cylinder 
depends upon the initial volume of the charge, 
the condition of the mixture, the compression 
pressure, the point of ignition, the speed of ex¬ 
pansion and the losses due to radiation. 

The losses due to improper expansion may 
therefore be decreased by making large valves 
and valve passages, but these often mean greater 
heat losses. The losses due to radiation may 
be reduced by increasing the temperature of the 
jacket water, and decreasing the area of the 
cylinder. But if the cylinder wall temperature 
is increased, there are considerable difficulties 
with lubrication, and the increased gain in 
thermal efficiency will be more than offset by 
the increased friction. 

In order to obtain the highest efficiency the 
difference in the temperature of the water en¬ 
tering and leaving the cylinder jacket should 
be a maximum. In practical tests it has been 
found that the best results are obtained when 
the jacket water is near the boiling point. 

Explosive Motors. Explosive motors are of 
three forms, known as stationary, marine and 
automobile. Their general characteristics are 


The Automobile Handbook 


293 


implied by their various designations. The sta¬ 
tionary motor may be either vertical or hori¬ 
zontal. Marine motors, designed for applica¬ 
tion to boats, are almost invariably vertical. 
Automobile motors are of comparatively recent 
introduction and of great variety, the aim of 
the designers being to secure the maximum of 
power and minimum of weight. They also 
may be vertical or horizontal. 

These three forms may be again divided into 
two-cycle and four-cycle types. In the former 
an explosion occurs at every revolution. In the 
latter there is an explosion at every alternate 
revolution. 

Explosive motors are dependent for success¬ 
ful operation on two things: First, a charge of 
gas or vapor, mixed with sufficient air to pro¬ 
duce an explosive mixture, and second, a 
method of firing the charge after it has been 
taken into the combustion chamber of the 
motor. 

When coal gas is used the supply is taken 
from the main and mixed directly with the nec¬ 
essary proportion of air. When gasoline is 
used, air is mixed with it in the correct pro¬ 
portion by carbureting devices. 

After the charge of gas and air has been 
taken into the cylinder it is compressed, as will 
be shown later, by the action of the motor itself 
and then fired, usually by an electric spark 
actuated by the motor, but sometimes by the 
use of a tube screwed into the cylinder and 


294 


The Automobile Handbook 


heated from the outside, the heat, of course, 
being communicated to the gas. The resulting 
explosion operates the motor. 

The principal parts of a four-cycle explosive 
motor are the cylinder, the piston, the piston 
rings which fit into grooves in the piston: two 
sets of valves, one to admit the charge and the 
other to permit it to escape after the explosion ; 
a crank shaft and connecting rod which con¬ 
nect it with the piston head, and a flywheel, 
whose presence insures steady running of the 
motor, and whose further functions will be 
better understood as the description proceeds. 
In the two-cycle form of motor there is really 
but one valve, the exhaust and admission-ports 
being covered and uncovered by the piston it¬ 
self. 

All of the parts referred to are’of the motor 
proper. Other parts, which are separate from 
the motor but on which its operation depends, 
are the carbureter, which supplies the charge 
of gasoline vapor and air for a gasoline motor, 
or a mixing chamber for mixing air arid gas in 
the case of a gas motor, and the batteries and 
other parts of the electrical ignition device. 

A part which has no connection with the 
actual running of the motor but with which 
practically all are fitted is the muffler, whose 
purpose is to deaden the sound of the explo¬ 
sion. 

The cylinders of all except very small motors 
are as a rule partly encased in a chamber 


The Automobile Handbook 


295 


through which water is circulated, the object 
of this being to keep the cylinder cook 

Two-Cycle Motor. The foregoing outline of 
the functions of the parts of the motor prepares 
us for a description of the two-cycle form of 
motor. This particular form of motor draws 
in a charge of gas or vapor, compresses it, fires 
it and discharges the product of combustion or 
burned gases while the crank makes but a sin- 



TWO-CYCLE MOTOR DIAGRAM 

Fig. 138 

o 

gle revolution and while the piston makes one 
complete travel backward and forward. 

Fig. 138 shows two sectional views—that is 
to say, views of the motor cut in two, longi¬ 
tudinally—of the principal parts of a two-cycle 
motor. Other parts, such as the crank shaft, 
connecting rod and flywheel, are omitted to 
avoid confusion. C is the crank case and A 
the admission valve, through which the vapor 


























296 


The Automobile Handbook 


passes to the crank case. B is the inlet pas¬ 
sage, through which it passes from the crank 
chamber to the cylinder. P is the piston. The 
igniter, which makes the electric spark when 
the lower point comes in contact with the up¬ 
per, is shown immediately below the cylinder 
cover. This causes the explosion of the vapor. 
E is the exhaust port, through which the burned 
charge escapes after the piston has been driven 
outward by the explosion and has reached the 
end of its stroke. 

Let it be supposed that the motor is still and 
the crank chamber C is full of gas or vapor. 
To start the motor the piston is started by 
means of a crank on the flywheel shaft, and as 
it passes to the position shown in the left-hand 
drawing it forces the charge of vapor through 
the port B into the cylinder. The piston then 
returns to the position shown in the right-hand 
view, moving away from the crank chamber C, 
and in doing so closes the port B and the ex¬ 
haust opening E and compresses the charge of 
vapor. The points of the igniter come together, 
a spark occurs and the resulting explosion 
forces the piston outward again. When the pis¬ 
ton reaches a point near the end of the stroke, 
as shown in the left-hand drawing, it uncovers 
the port E and the burned charge passes out, 
the new charge coming through the port B im- 

m ed i a tel v afterwa rd s. 

•/ 

The admission of the new charge to the crank 
chamber is controlled by the action of the pis- 


The Automobile Handbook 


297 


ton. As the latter travels outward it has a 

tendency to create a vacuum in the crank 
*/ 

chamber. This draws the valve inward and 
admits the charge of vapor. 

It will be observed that there is a projection 
on the head of the piston. This is generally 
known as a baffle-plate. Its object is to pre¬ 
vent the incoming charge from passing di¬ 
rectly across the cylinder and out at the ex- 

^ " ■ ■ — ■ — — ... . . - ■ ■ - -■■■ . . ■ ■ - i 



FOUR-CYCLE MOTOR DIAGRAM 

Fig. 139 

haust port E. which, it will be observed, is di¬ 
rectly opposite it. The baffle-plate directs the 
incoming charge toward the combustion cham¬ 
ber end of the cylinder, providing as nearly as 
may be, a pure charge of vapor and assisting 
in the expulsion of the remainder of the burned 
gases remaining in the cylinder as a result of 
the last explosion. 

Four-Cycle Motor. Fig. 139 furnishes two 



























298 


The Automobile Handbook 


sectional views of a four-cycle type of motor 
with some of the parts removed, as in Fig. 138. 
It shows a cylinder C, admission-valve A, a 
piston P, and exhaust-valve E in place of the 
exhaust-port E in Fig. 138. 

The left-hand view shows the piston P about 
to suck in a charge of vapor, by the same 
method as previousy described, through the 
admission-valve A into the cylinder C. The suc¬ 
tion continues until the piston P reaches the 
position Mi own in the right-hand view. Then 
the piston returns until it again arrives at the 
position shown in the left-hand view, compress¬ 
ing the charge of mixture during this operation. 
Just before the piston arrives at the end of its 
travel in this direction, the charge of vapor, 
now under compression, is ignited by the 
method previously explained and its expansion 
forces the piston back to the position shown in 
the right-hand view. When the piston has, for 
the second time, reached the position shown in 
the right-hand drawing, a mechanical device 
opens the exhaust-valve. The exhaust-valve 
remains' open until the piston has again arrived 
at the position in the left-hand view. Then it 
closes, the piston again commences to draw in 
a charge of vapor and the cycle of operation 
of the motor is repeated. 

Fans for Cooling. Fans used for cooling cyl¬ 
inders are of various designs, most of them hav¬ 
ing four, five, or six blades. The average speed 
of revolution is about one and one-half times 


The Automobile Handbook 


299 


the speed of the engine. In some instances fly¬ 
wheel fans, similar to the one shown in Fig. 
140 are used, in which dase they need a tight 
bonnet, and under pan. In the Lanchester 
method of air cooling two aluminum fans are 



Fig. 140 
Fly-Wheel Fan 


friction-driven by the fly-wheel between them, 
and suck the air from between the flanges cast 
on the two cylinders into the wind chest and 
thence into the centre of the fans, the air then 
being ejected by centrifugal force at the per- 
































































300 


TJte Automobile Handbook 


iphery. The fans consume but little power, and 
discharge the heated air quite away from the 
motor. 

Fiber, Vulcanized. Paper-pulp treated with 
sulphuric acid, washed and afterwards com¬ 
pressed into sheet or rod form, is known as vul¬ 
canized fiber. 





Fig. 141 

Five-Plate Clutch 

Five-plate Clutch. In the matter of the num¬ 
ber of plates in the disc clutch there is no agree¬ 
ment between designers. Some use a very large 
number of thin plates, as many as fifty or sixty, 
and others use a verv small number, as few as 
six or eight; in fact, it may be said that the sin¬ 
gle disc clutch, which has only two frictional 
surfaces, is the lower limit. One arrangement 



















































































The Automobile Handbook 


301 


which uses five plates is shown in Fig. 141. The 
diameter of the clutch is somewhat smaller 
than that of the single or three-plate types, but 
its diameter must be quite large in order to 
transmit considerable horse power. 

Floating Axle. In a full-floating axle the 
entire weight of the rear end of the car is car¬ 
ried on the axle housing, or casing, leaving the 
drive-shafts in the axle with no other work than 
that of revolving the wheels. In this axle, by 
the removal of the hub caps, the drive-shaft in 
each half of the axle can be pulled out, owing 
to its being free in the housing, and having gen¬ 
erally a squared end which fits into the bevel 
gears of the differential. In a semi-floating rear 
axle the complete car weight at the rear is car¬ 
ried on the axle housing, identically as in the 
floating axle, but the drive-shafts of the axle 
are not removable by pulling endwise through 
the hub. This is because these shafts are tightly 
keyed at their inner ends with differentials, 
bevels or, as is the case in one or two cars, the 
bevel gear is formed integrally with the shaft. 

Fluxes for Soldering. Some good fluxes for 
soldering purposes are: 

Iron or steel.Borax or sal-ammoniac. 

Tinned iron .Resin or chloride of zinc. 

Topper to iron .Resin. 

Iron to zinc .Chloride of zinc.* 

Galvanized iron .Mutton tallow or resin. 

Copper or brass .Sal-ammoniac or chloride of zinc. 

j j( >ad .Mutton tallow. 

Block tin .Resin or sweet oil. 

♦Chloride of zinc is simply zinc dissolved in hydrochloric 
(muriatic) acid, until the acid is cut or killed. 








302 


The Automobile Handbook 


Flywheels. One of the first and most impor¬ 
tant considerations in connection with the con¬ 
struction of a gasoline automobile motor is the 
proper diameter and weight of the flywheel. If 
the diameter and weight of the flywheel be 
known, the speed of the motor or its degree of 
compression will become a variable quantity. 
On the other hand, if the speed of the motor 
and the degree of compression be fixed, the di¬ 
ameter or weight of the flywheel rim must be 
varied to suit the other conditions. If the speed 
of the motor and its degree of compression be 
known, the diameter of the flywheel or the 
weight of the flywheel rim may be readily as¬ 
certained from the following formulas. 

Weight of Rims of Flywheels. The weight 
of the rim of the flywheel is the only portion 
which enters into the following calculations, the 
weight of the web, or spokes and hub being 
neglected. 

Let M.P be the mean pressure of the com¬ 
pression, and A the area of the cylinder in 
square inches. If S be the stroke of the piston 
in inches, and N the number of revolutions per 
minute of the motor, let D be the outside diam¬ 
eter of the flywheel in inches and W its re¬ 
quired weight in pounds, then 

M.P X A X S X N 

W =- 

2560 X D 

Diameter of Rtms of Flywheels. A motor 



The Automobile Handbook 


303 


that is intended to operate at a slow rate of 
speed, and consequently with a high degree of 
compression, will require a flywheel of much 
greater diameter and weight than a high speed 
motor of the same bore and stroke. It may be 
well to remember that within certain limita¬ 
tions the diameter and weight of a flywheel 
should be as small as is possible, as an increase 
in either means a reduction in motor speed, and 
a consequent loss of power. 

To ascertain the diameter of a flywheel 
when all other conditions are known, if D be 
the required diameter of the flywheel in inches, 
then 

M.P X A X S X N 

D =- 

2560 X W 

AV eight of Rims of Flywheels with a Given 
Fluctuation in Speed. If it be desired to run 
a motor at a practically uniform speed and 
with only a slight fluctuation or variation in 
the velocity of the flywheel, if W be the re¬ 
quired weight of the flywheel and x be the al¬ 
lowable fluctuation of the flywheel in revolu¬ 
tions per minute above and below its normal 
speed, then 

M.P X A X S X N 
W = -- 

365 X x 

Horsepower Stored in Rims of Flywheels. 
It is sometimes desirable to know the amount of 




804 


The Automobile Handbook 


energy or horsepower which may be stored in 
the rim of a flywheel of known diameter and 
weight, with a given speed. If H.P be the 
horsepower stored in the rim of the flywheel, 
then 

D 2 X W X N 

H.P =- 

792,000 

Safe Speed for Rims of Flywheels. The safe 
velocity for the rim of a cast iron wheel is 
taken at 80 feet per second. Let N be safe 
speed of the flywheel in revolutions per minute, 
then 

18,335 
N —- 

D 

The mean pressures corresponding to vary¬ 
ing degrees of compression may be found by 
reference to Table 2. 

M.P =: Mean pressure. 

A = Area of cylinder in square inches,, 

S = Stroke of piston in inches. 

N — Number of revolutions per minute. 

I) = Diameter of flywheel in inches. 

W = Weight of flywheel in pounds. 

Balancing with the Reciprocating Parts of 
the Motor. The flywheel should be balanced 
as accurately as is possible before mounting 
on the crank shaft. In the first place set the 
crank shaft on two perfectly straight parallel 
bars, one bar under each end. Then attach the 




The Automobile Handbook 


305 


connecting rod and piston to the crank and 
turn the shaft until the crank jaws are parallel 
with the floor or in other words at right angles 
to a perpendicular line drawn through the cen¬ 
ter of the shaft. Place a scale under the crank 
pin, or use a hanging scale attached to some 
rigid support above the pin and connect it to 



Fig. 142 

Four-Cylinder Engine 


the crank pin by a wire or cord sufficiently 
strong to carry the weight. Then find the 
weight of the parts according to the scale and 
attach the same amount to the flywheel at the 
same distance from the shaft on the side oppo¬ 
site the crank, and the result will be a fairly 
balanced motor. It is impossible to obtain a 
perfect balance, but the above method will as- 















































306 


The Automobile Handbook 


sist greatly in reducing the vibration of the 
motor. 

Four-cycle Motor, Operation of. A four-cy¬ 
cle motor has only one working stroke or im¬ 
pulse for each two revolutions. During these 
two revolutions which complete the cycle of 
the motor, six operations are performed: * 

1. Admission of an explosive charge of gas, 
or gasoline vapor and air to the motor-cylinder. 

2. Compression of the explosive charge. 

3. Ignition of the compressed charge by a 
hot tube, or an electric spark. 

4. Explosion or extremely sudden rise in the 
pressure of the compressed charge, from the 
increase in temperature after ignition. 

5. Expansion of the burning charge during 
the working stroke of the motor-piston. 

6. Exhaust or expulsion of the burned gases 
from the motor-cylinder. 

Four-Cylinder Engines. Fig. 142 is an out¬ 
line view of a four cylinder gasoline engine, 
showing the position of the pistons and cranks 
relative to each other. In this type of motor 
the cylinders are generally placed side by side 
as shown in Fig. 142, although some forms of 
runabouts use the four cylinder opposed set¬ 
ting. In the four cylinder engine each piston 
is at all times one stroke behind its predeces¬ 
sor; as for instance, when explosion occurs be¬ 
hind piston 1, piston 2 is compressing, piston 3 
is drawing in its charge, and the expanded gas 
is being exhausted from behind piston 4. The 


The Automobile Handbook 


307 


development of power is therefore continuous, 
there being at all times one piston on the work¬ 
ing stroke. In a four cylinder engine there are 
always two pistons moving in one direction, 
while the other two are moving in the opposite 
direction. This uniformity of movement pre¬ 
vents shock, and the motor may be made verv 
light in proportion to power capacity. The 
majority of automobiles are equipped with this 
type of engine. 

Frame—Sagged, How to Straighten. A 

frame which is sagged to the extent of perma¬ 
nent deformation can be restored to approxi¬ 
mate straightness by heating it in a charcoal 
fire with an air blast. To do this properly it 
will most likely be necessary to cut out the riv¬ 
ets, so the side members can be handled inde¬ 
pendently. A good plan of procedure is to in¬ 
close the bent portion of the frame in a section 
of stove pipe of sufficient size in which the 
charcoal fire is built. A length of 1-inch gas 
pipe, closed at one end and having 5/16-inch 
holes, drilled at intervals of about 6 inches, is 
laid in the bottom of the pipe and furnishes the 
air supply from a bellows. When the charcoal 
fire is well kindled, the frame is introduced up¬ 
side down and is supported at the ends. The 
fire is then concentrated on the bent portion, 
and as the frame becomes hot it will straighten 
itself. It must be watched carefully and the 
air blast stopped as soon as the frame is seen to 
be straight. Most of the frames used in Amer- 


308 


The Automobile Handbook 


ican cars are ordinary carbon steel and require 
no special treatment. It will be well, however, 
on stopping the air blast to shift the stove pipe 
to a cooler portion of the frame, to permit the 



part which has been straightened to cool as 
quickly as exposure to the air will permit. A 
frame which has been sagged and straightened 
in this manner will require to be trussed to pre¬ 
vent recurrence of the trouble. As conditions 


























The Automobile Handbook 


309 


vary so much the best rule to follow is to ob¬ 
serve the truss arrangement on some similar 
ear. The struts should be about 4 or 5 inches 
long, and should be located at the spots where 
the sagging has occurred. The truss rod itself 
should be about % inch in diameter, and drawn 
taut by a turnbuckle, which may be finally 
tightened when the chassis has been assembled. 

Frame Hangers. Since the inception of the 
automobile, the frame or running gear of the 
car is in nearly all cases attached to the springs 
and the body carried upon the frame. The parts, 
or in some cases actually extensions of the 
frame are, or should be properly termed frame- 
hangers, but they are erroneously and almost 
universally known as body-hangers, from the 
term applied to the constructions used in horse- 
drawn vehicles. Some forms of frame-hangers 
are of pressed steel construction, but the usual 
forms are made of drop-forgings. Figure 143 
shows some of the forms of drop-forged frame- 
hangers for automobile use: The front or what 
is generally known as the pump-handle form 
of hanger is shown at J, the rear or fish-hook 
form is shown at K and the forms of hangers 
used for attaching the inner ends of the springs 
to the frame are shown at L and M. 

Franklin Carbureter. The Franklin Carbu¬ 
reter is of the float feed type. The supply of 
gasoline is controlled by a T handle connected 
with the valve, and passing to the dash within 


310 


The Automobile Handbook 


easy reach of the operator. There is also a 
primer attached, to be used in starting. 

The throttle, and by pass valves work to¬ 
gether, and thus insure a perfect mixture of 
gasoline and air at all times. The working of 
these valves, the securing of the correct amount 
of warm air, and the entire absence of springs, 
result in a uniformity of work under varying 
conditions. 

Friction. Friction, being the resistance to 
motion of two bodies in contact, depends upon 
the following laws: It will vary in proportion 
to the pressure on the surfaces; it increases 
with the roughness of the surface; friction of 
rest is greater than friction of motion; the to¬ 
tal friction is independent of the area of the 
contact surfaces when the pressure and speed 
remain constant; and friction is greater be¬ 
tween soft bodies than hard ones. 

The behavior of lubricated surfaces is cpiite 
different-from dry ones, the laws of fluid fric¬ 
tion being independent of the pressure between 
the surfaces in contact, but it is proportional to 
the density of the fluid and in some manner to 
the viscosity. When a bearing is thoroughly 
lubricated it does not seem to make much dif¬ 
ference what the metals are, because there is a 
layer of oil running around with the journal 
and sliding over another layer adhering to the 
bearing. If, however, the feed fails, or the pres¬ 
sure gets too heavy for the nature of the lubri¬ 
cant, and so squeezes it out, or the temperature 


The Automobile Handbook 


311 


lias risen so high as to affect the body of the 
oil, then the surfaces come into contact and the 
peculiar nature of the contact asserts itself, 
some combinations abrading and seizing more 
readily than others. When the lubrication is 
thorough, the condition of the fluid friction be¬ 
ing realized, the intensity of the load makes less 
difference than would be expected. 

Friction Drive. For power transmission un¬ 
der conditions where the load is constant and 
uniform the friction (Jrive shows a high effi¬ 
ciency,. but such conditions do not as a rule 
exist with the automobile. Where the slip ex¬ 
ceeds 4 per cent, the drive falls off considera¬ 
bly in efficiency, and as the conditions of ser¬ 
vice in automobile work are about the worst 
imaginable it would appear to be difficult to 
prevent this. The load is never constant for 
any length of time, and it is about as far from 
being uniform as it possibly can be. Still the 
friction drive has proven considerable of a suc¬ 
cess on a number of light cars, and the experi¬ 
ence of the manufacturers of the latter would 
seem to show that even under such very ad¬ 
verse circumstances as the necessity for pulling 
a car out of a hole, or starting from dead on a 
very steep hill, the friction drive has been able 
to acquit itself with credit. 

Fuels for Automobiles. Apart from the pos¬ 
sibility of an increase in the fuel resources of 
the world due to some revolutionary discovery, 
the ingredients in any mixed fuel for automo- 


The Automobile Handbook 


312 

bile use must be confined to the following list, 
in which, for completeness, gasoline is in¬ 
cluded : 

Gasoline. Average composition, C=84, 11 = 
16. 

Source, petroleum. 

Boiling point, 50° to 150° Cent. 

Specific gravity, .680 to .720. 

Calorific value, 19,000 B. T, U. 

Latent heat, small. 

Benzine. Average composition, C=92, H 

= 8 . 

Source, coal tar. 

Boiling point, 80° Cent. 

Freezing point, 5° Cent. 

Specific gravity, .899. 

Calorific value, 19,000 B. T. U. 

Latent heat, small. ^ 

Alcohol. Average composition, C=32, H=8, 
0=35. 

Source, vegetable matter, principally corn, 
beets, potatoes, sugar cane. 

Boiling point, 70° Cent. 

Specific gravity, .806. 

Calorific value, 12,600 B. T. U. 

Latent heat, considerable. 

Tar Benzol. Average composition, C=92, 
H=8. 

Source, a by-product in the manufacture of 
coke. 

Boiling point, 80° to 120° Cent. 

Specific gravity, .895. 


The Automobile Handbook 


313 


Calorific value, 19,000 B. T. U. 

Latent heat, small. 

Kerosene. Average composition, C=85, 
H=15. 

Source, petroleum. 

Boiling point, 150° to 300° Cent. 

Specific gravity, .800 to .825. 

Calorific value, 19,000 B. T. U. 

Latent heat, considerable. 

Motor Spirit, Naphtha, Benzoline, Benzine. 
Average compositnon, C=85, H=15. 

Source, petroleum and shale. 

Boiling point, 60° to 160° Cent. 

Specific gravity, .750. 

Calorific value, 19,000 B. T. U. 

Latent heat, appreciable. 

Methyl Alcohol, Wood Spirit, Naphtha. Av¬ 
erage composition. C=38, 11=12, 0=50. 

Source, the distillation of wood. 

Boiling point, 66° Cent. 

Specific gravity, .812. 

Calorific value, 9,600 B. T. U. 

Latent heat, appreciable. 

Acetylene Ethene. Average composition, 
C=92, 11=8. 

Calorific value, 25,000 B. T. IT. 

Fuel Consumption of a Two-Cycle Motor. 

The two-cycle engine uses more fuel than the 
four-cycle. The greater consumption is not so 
much due to the fact that the two-cycle motor 
makes an explosion for every revolution, in • 
contrast with the missed stroke of the four-cy- 


The Automobile Handbook 


314 

ele, as it is to the fact that there is considera¬ 
ble retention in the cylinder of the exhaust 
charge, and that, despite the deflector, more or 
less of the fresh charge escapes at the exhaust. 
The two-cycle is also harder on a battery owing 
to the greater frequency of the demands upon 
it. but with improved methods of ignition, even 
dry batteries have been found to give very sat¬ 
isfactory service. 

G. and A. Carbureter. This carbureter has 
no springs, but has a separate float chamber, 
and a peculiar form of ball valve for an extra 
air supply. 

The air passage is a Venturi tube, resembling 
the hour glass in shape. Air enters through the 
screened lower end, and gasoline is admitted 
through an angling pipe at the small diameter 
center, there being no needle valve in the nozzle. 
The size of the nozzle is mathematically calcu¬ 
lated in proportion to the capacity of the mo¬ 
tor, as is also the size of the Venturi shaped air 
passage. To the top of the air passage is se¬ 
cured a drum portion, in which is a rotating 
throttle. Interposed between the top of the 
Venturi tube, and the throttle chamber there 
is an expansion in the bottom of which is a se¬ 
ries of holes of various sizes, and resting in 
each is a metal ball. These balls being of dif¬ 
ferent weights it follows that, when a sufficient 
supply of air cannot enter through the Venturi 
tube, the pull of air will lift, first the lighter 


The Automobile Handbook 


315 


balls, and as this pull increases the heavier balls 
will be raised. 

The Gaeth Carbureter. The Gaeth Carbu¬ 
reter is of the separate float chamber type, and 
the mixing chamber is a vertical cylinder 
through the center, which is completely filled 
by a needle valve which turns when the engine 
is throttled. All the air comes up from below 
and passes around the needle. At the base of 
the needle are V shaped openings, which regu¬ 
late the admission of the air. In the side of the 
needle are openings for controlling the passage 
of the outgoing mixture, a partial turn of the 
needle also affecting a part movement of the 
needle valve in the nozzle, so that with no air 
there is an increased flow of gasoline. 

This carbureter may be set for slow running, 
and needs no other advancement for high 
speeds. The device is controlled in three ways. 

First—by the entering air. 

Second—by the entering gasoline. 

Third—by the mixture passing to the motor, 
all being under control of the driver by means 
of a lever at the top of the starting wheel. 

Garage—Cleaning Floors. A hot saturated 
solution of common washing soda will do very 
well. This can be made up in quantities and 
stored against future use. If this method is 
used, be sure to reheat it before using, the boil¬ 
ing point being about right. Since that will be 
too hot to apply with the hands, use any old 
broom or brush to “slosh’’ it around on the 


316 


The'Automobile Handbook 


floor. An equally good, if not better, solution to 
use for this purpose is trisulphate of sodium, 
marketed by several chemical companies, and 
sold at from four to five cents per pound at re¬ 
tail. This can be used cold and will not injure 
tlie most delicate hands; on the other hand, it 
will clean them very thoroughly, so that users 
of this solution use it for the hands as well as 
for the floors. This is strong, however, and 
may be used to remove paint. 

Protection From Fire. The recommenda¬ 
tions of the National Fire Protection Associa¬ 
tion pertaining to garages and their operation 
are as follows: No dynamo or gas engine should 
be permitted where gasoline is stored or ham 
died; all exposed lights should be eliminated; 
cleaning of acetylene lamps and removal or re¬ 
newing of carbide should be carried on outside 
of garage; the residue of acetylene lamps 
should never be cast on the floor; machines 
should have oil tanks emptied before being put 
in the repair shop; the use of extension electric 
wires is condemned, as they may cause fire; mo¬ 
tor testing should be done outside, for sparks 
might ignite the fumes of gasoline; storage 
tanks should be filled from outside of garage; 
all volatile oils should be stored in good, heavy 
tanks under ground, as far away from the 
building as possible; pipes for filling storage 
tanks should not pass through the garage in 
any way; a filling station should be twenty to 
thirty feet from the entrance to the garage, and 


The Automobile Handbook 


317 


tanks of cars filled from there if it is necessary 
to fill them when the cars are inside of the gar- 
age; furthermore, the station should be fire¬ 
proof, and all cars should be brought to this 
point for filling; smoking and carrying of 



bb* 



matches, or use thereof should be strictly pro¬ 
hibited ; floors should be kept free of oil drip¬ 
pings, and pails of sand should be kept handy 
in proximity to gasoline. 

Gardner Magneto Self-starter. An automo¬ 
bile fitted with this device can be started from 






















318 


The Automobile Handbook 


the seat by pushing a pedal or button. As 
shown in Fig. 144, it consists of four parts, all 
of which are attached to the transmission shaft. 
The arrangement consists of a spiral spring, 
which is wound by the momentum of the car 
when the car is running, and this tension is 
available the next time the car needs to be 
started. By pushing a pedal a clutch is ac¬ 
tuated, which releases the spring and causes 
the engine shaft to be revolved, fifteen or 
twenty turns, which is more than sufficient to 
fill the cylinders with gas and create sufficient 
magneto voltage to give a good spark. 

Gases, Expansion of. All gases expand 
equally, 1/273 part of their volume for each 
degree of temperature, Centigrade, or 1/491 
. part of their volume for each degree of temper¬ 
ature, Fahrenheit. 

Gas Producer for Automobiles. Homogene¬ 
ity is a property which is difficult of attain¬ 
ment in mixtures of gasoline and air out of a 
carbureter of the conventional float-feed type, 
unless the gasoline is volatile in the extreme, 
and this is not likely to be true if the gasoline 
is a mechanical mixture of a number of the 
fractional distillates due to the range of tem¬ 
perature, in the distilling process, which is said 
to obtain at the present time. It is claimed that 
the present practice in the production of gaso¬ 
line is to use all the fractions between 50 and 
150 deg. C. 

Hexane, the formula of which is C 0 H 14 , is ad- 


The Automobile Handbook 


319 


mitted to be the superior fraction of all the 
distillates from the crude oil used in the pro¬ 
duction of gasoline, and while the distillers 
would like to have credit for using nothing but 
the best for the purpose, the fact remains that 
gasoline of the present time can scarcely be 
classed as hexane, nor does it seem to hold any 
more hexane than the amount required to assist 
in cranking a cold motor, it being the case that 
a motor could not be started “cold” in the ab¬ 
sence of some of the more volatile of the hydro¬ 
carbons. 

Carbon in Cylinders Due to Gasoline Used. 

Lubricating oil is charged with the crime of 
depositing carbon on the surfaces of the com¬ 
bustion chamber, and this carbon in turn causes 
‘ ‘bucking,’’ and pre-ignition. It probably is true 
that inferior cylinder lubricating oil will de¬ 
posit carbon, to some extent, but the main trou¬ 
ble is from the gasoline which will not vaporize 
until it is allowed to contact with the hot cyl¬ 
inder walls, and this process of reducing the 
gasoline to vapor is bound to lead to a carbon 
deposit for the same reason that wood is 
“coked” if it is heated to a temperature of 
about 650 deg. C., provided the amount of air 
present is less than that which would cause 
complete combustion. 

To a very considerable extent the trouble is 
aborted by preheating the mixture on its way 
to the combustion chamber, or if the air is 
heated sufficiently before it enters the earbu- 



320 


The Automobile Handbook 


reter. The time was when this process worked 
very well, indeed, but it is becoming more diffi¬ 
cult every day to so heat the air, or the mixture, 
that globules of gasoline will not enter the cyl¬ 
inders and coke up. The amount of heat re¬ 
quired for the purpose is vastly more than is 
generally well understood, and unless enough 
heat is supplied, the result will be a crop of 
carbon in the combustion chamber. 

Any process that will manufacture a homo¬ 
geneous gas to the entire exclusion of liquid 
gasoline will serve the purpose, and preheating 
the mixture is a step the right direction. 
The time was when autoists hoped that illum¬ 
inating gas could be put under compression 
and that enough of it could be carried in a tank 
of reasonable size to accomplish the work. It 
is generally understood that illuminating gas 
will serve well for the purpose, but it is not 
possible to store enough of the gas to enable a 
car to travel far without having to replenish 
the tank. 

That the gas-tank idea clings to the automo¬ 
bile with a tenacity which augurs for inherent 
utility will be seen in the illustrations here of¬ 
fered. Fig. 144a shows a gas tank and the 
manner in which it is connected up to a six-cyl¬ 
inder car in which it will be noticed that the 
carbureter is entirely dispensed with. The en¬ 
tire absence of a carbureter is the best indica¬ 
tion of the change over from liquid gasoline to 
gas, and it is the manufacture of this gas, as it 


The Automobile Handbook 


O A 











































































The Automobile Handbook 


QOO 

is needed for the motor, that will be given at¬ 
tention at this time. 

The gas producer consists essentially of a 
copper tank, or container, about the size of the 
conventional gasoline tank; located in any con¬ 
venient place, as under the seat of the driver, 
which tank is filled with laminae of wood-pulp 
sheets, superimposed. Each sheet is about % 
inch thick, of rectangular shape, and drilled 
full of holes, each about % inch in diameter, 
and spaced about 1% inches apart. The sheets 
of wood pulp are separated from each other 
about the thickness of one of the laminae, and 
the nests of sheets are in two sections. 

Between the two sections of the nests of 
wood-pulp sheets the space is taken by a heater 
for the air as it enters on its way to the gaso¬ 
line-saturated wood-pulp sheets. The heater 
is made up of a coil of piping in a manner not 
unlike the radiators used in steam-heating 
work. The exhaust gases from the motor serve 
to convey the heat to the radiator. The air en¬ 
ters at the top, passes through the heater coil 
to the under side of the nests of wood-pulp 
boards. The admission of air through a check 
valve, and the suction of the motor, furnishes 
the required difference in air pressure, so that 
the air is sucked in. 

Since the air cannot turn back through the 
check valve, it must pass up through the nest 
of pulp boards, and the holes in the boards fur¬ 
nish the openings, as well as a large surface. 


The Automobile Handbook 


323 


Fig*. 145 Shows the top of the container cut 
away, exposing the top layer of pulp boards to 
view, and the small holes will be noticed. The 
same figure shows the heater in the middle of 
the container, and Fig. 146 is offered to more 
clearly bring out the construction features of 
the system. The cross section of the container, 



Fig. 145 

Generator with Top Cut Away to Show Holes in 

Pulp Filling 

as shown in Fig. 146, indicates that there is but 
very little free space in the same, and in the 
process the gasoline is spilled into the top of 
the tank in sufficient quantity to saturate the 
wood-pulp mass. 

The quantity of gasoline required is about 
60 per cent of the amount that the tank would 









































324 


The Automobile Handbook 


hold, provided the wood pulp were not present. 
Excess gasoline is not required, and in the 
process, the heated air as it passes up through 
the holes in the pulp boards wipes vapor of gas¬ 
oline oft' of the surfaces, and owing to the 
heated condition of the air, it is in condition to 
become enriched, even if the gasoline is of poor 



Fig. 146 

.Section Showing Nest of Boards with Spaces Between. 

quality. By means of a valve designed for the 
purpose the rich mixture is diluted after it 
leaves the tank, and the motor is enabled to 
draw the mixture of homogeneous gas suited 
for its needs, while the driver is enabled to 
alter the proportions at will, according to 
road conditions, atmospheric influences, and 
properties of the gasoline, as the supply reduces 









































































The Automobile Handbook 


325 


in the tank, leaving the heavier residuum. 
There can be no explosion of the gas in the 
tank for the reason that the gas is not suffi¬ 
ciently diluted with air to render it explosive. 

Gasoline, How Obtained. Benzine, Gasoline, 
Kerosene and the kindred hydro-carbons are 
products of crude petroleum. 

They are separated from the crude oil by a 
process of distillation. The process is very sim¬ 
ilar to that of generating steam from water. 

Crude petroleum subjected to heat will give 
off in the form of vapor such products as Ben¬ 
zine, Gasoline and Kerosene, etc. The degrees 
of heat at ivhich these products are separated 
are comparatively low. Various degrees of heat * 
will separate the distinct products. As a means 
of illustration, it may be said that the crude oil 
when raised to certain temperatures gives off 
vapors which when cooled liquefy into what 
are known as Benzine, Gasoline and Kerosene. 

Viscosity of Gasoline. It is a mistake to 
assume that because gasoline does not thicken 
up, it is retarded in its How through the nozzle 
of the carbureter. Taking gasoline having a 
specific gravity of 0.71 the quantity that will 
pass through the nozzle of a carbureter under a 
given pressure will increase as the temperature 
is increased, as shown in the following table: 


Temp, decrees F. 

50°. 

59°. 

68 °. 

77°. 

86 °. 

95°. 


Relative Flow. 
. . . 1 
. . . 1.073 
. . . 1.145 
, . . 1.212 
, . . 1.27 
, . . 1.335 








326 


The Automobile Handbook 


Since carbureter nozzles are not readily ad¬ 
justable, nor with any degree of certainty, it 
follows from the above that the influence of tem¬ 
perature upon the weight of fuel ejected will 
most certainly affect the efficiency of the car¬ 
bureter. This source of trouble goes to indi¬ 
cate that some means of maintaining a constant 
temperature is of the greatest advantage, and 
in a measure it argues for the adaptation of 
water (hot) jacketing, not around the depres¬ 
sion chamber, as is usually the practice, but 
around the gasoline (float) bowl, in order to 
maintain a constant temperature of the liquid 
gasoline as it flows through the nozzle. 

Gasoline Explosions. There are two entirely 
different kinds of explosion, which would un¬ 
doubtedly both be referred to as gasoline ex- 
idosions. The real gasoline explosion is the 
kind taking place in the cylinder of a gasoline 
motor, in which heat and pressure are suddenly 
produced by the combustion of gasoline vapor 
in air. The other kind of explosion referred to 
may be explained as follows: 

If a tank of gasoline be placed on a woodpile 
and the latter set on fire, the heat would 
raise a pressure in the tank, which would rap¬ 
idly increase and the tank would finally explode 
from the pressure. The gasoline would then 
be thrown in all directions, and, owing to its 
superheated condition, the greater part of it 
at least would instantly vaporize, mix with the 


The Automobile Handbook 


327 


air of the atmosphere and be ignited by the 
flame which caused the explosion. 

Gasoline Fires, Extinguishing. A number of 
fires have been caused by leaky gasoline pipes 
on automobiles, and many persons would like to 
know of chemicals which can be used to put 
out such fires. Water is exceedingly danger¬ 
ous to use, and it is not always possible to get 
at the fire to smother it with wet rags or waste. 

In case of fire due to gasoline, use fine earth, 
flour or sand on top of the burning liquid. 

A dry powder can be used for this purpose 
which w T ill extinguish the fire in a few seconds. 
It is made as follows: Common salt, 15 parts— 
sal-ammoniac, 15 parts—bicarbonate of soda, 
20 parts. The ingredients should be thoroughly 
mixed together and passed through a fine mesh 
sieve to secure a homogeneous mixture. 

If by any chance a tank of gasoline takes fire 
at a small outlet or leak, run to the tank and 
not away from it, and either blow or pat the 
flame out. Never put water on burning gaso¬ 
line or oil, the gasoline or oil will float on top 
of the water and the flames spread much more 
rapidly. 

Several gallons of ammonia, thrown in the 
room with such force as to break the bottles 
which contain it, will soon smother the strong¬ 
est fire if the room be kept closed. 

Gasoline Motor Construction. When design¬ 
ing a gasoline automobile motor, the first ques¬ 
tion that will arise is as to the proper number 


The Automobile Handbook 


328 

t 

of cylinders. The question as to the proper 
number of cylinders for an explosive motor may 
be briefly summed up as follows: A single cyl¬ 
inder has the merit of simplicity, and requires 
less mechanism to operate it, but tends towards 
excessive vibration. Multi-cylinders develop 
more power with less weight and reduce the 
motor vibration and strain, and have also other 
advantages over a single cylinder. The ques¬ 
tion therefore is: How many cylinders are best 
in practice ? To give the best results, a two- 
cylinder motor should, if the cranks are op¬ 
posed, have its cylinders in axial alignment in 
order to ensure a uniform impulse. If the 
cranks and cylinders are opposed it is possible 
to obtain correct mechanical balance of con¬ 
necting rods and pistons, and vibration is thus 
diminished. If the cylinders are of the twin 
form with the cranks opposed, explosions will 
necessarily follow each other at a half revolu¬ 
tion, and one and a half revolutions apart. This 
gives irregular impulses which tend to set up 
vibration. The next best construction is three 
cylinders, with the cylinders parallel, and the 
cranks set at an angle of 120 degrees. This gives 
regular impulses two-thirds of a revolution 
apart, and consequently a more uniform strain 
on the parts, and reduces vibration. 

A four-cylinder motor has greater advant¬ 
ages of mechanical balance than the three-cyl¬ 
inder form, but on the other hand, by reason 
of the greater amount of exposed cylinder wall 


The Automobile Handbook 


329 


for a given capacity, it is not as economical in 
fuel consumption. The greater advantage of 
four as compared with the three cylinders, is a 
greater division of the impulses, reducing vi¬ 
bration to a minimum. 

Other points to be considered in the design 
of a motor are: 

The proper arrangement or location of all 
working parts so as to be readily accessible for 
repair or adjustment. 

Practically automatic lubrication of the mo¬ 
tor. 

The best and simplest method of operating 
the admission and exhaust-valves. 

The proper diameter and weight of flywheel, 
and a practically correct balance of the recipro¬ 
cating parts of the motor. 

The best and most reliable system of ignition, 
with a view to eliminating ignition troubles. 

The most economical type of carbureter, and 
one that will require the least attention. 

And last, but not least, reduction of weight, 
simplicity of construction and good mechanical 
design. 

In the construction of motor cylinders ex¬ 
perience has clearly established one point—that 
the cvlinder, with its combustion and valve- 
chambers, should be integral or in one piece, 
and that no joints closed by gaskets should ex¬ 
ist back of the head of the piston. While all 
manufacturers do not adhere to this rule, it is a 
fact that many difficulties have been experi- 


330 


The Automobile Handbook 



Fig. 147 

Vertical Cylinder, Water-Cooled Gasoline Motor 


1. Admission valve. 

2. Spark plug. 

3. Exhaust valve. 

4. Rotary pump. 

5. Cam shaft. 

6. Crank case. 


7. Crank shaft. 

8. Crank pin. 

9. Connecting rod. 

10. Cylinder. 

11. Piston and rings. 

12. Oil tank. 











































The Automobile Handbook 


331 


eneed with leaky joints, and that the plan of 
avoiding- them altogether should be followed. 

Figure 147 shows a vertical cross-section of a 
gasoline automobile motor of the most ap¬ 
proved modern type. It has automatic lubrica- 



Fig. 148 

Vertical Four-Cylinder Motor 
With Mechanically Operated Admission-Valves With 
Automatic Throttling Governor 

tion, detachable inlet or admission-valve and 
rotary pump for the water circulating system. 

Figure 148 illustrates a modern type of verti¬ 
cal four-cylinder gasoline automobile motor, 
having the admission-valves automatically 
throttled by means of a centrifugal governor 
^n the end of the cam-shaft, as shown in the 































































































332 


The Automobile Handbook 


drawing. The admission-valves are mechanic¬ 
ally operated. 

While the cooling of the cylinder of an ex¬ 
plosive motor is most successfully accomplished 
by means of a water-circulating system, a num¬ 
ber of up-to-date cars successfully use cooling 
devices other than water. The success of air 
cooling for explosive motors is due in most 
cases to the use of a number of ribs cast in¬ 
tegral with the cylinder and having a large 
radiating surface. 

Gasoline Motor, Fuel Consumption of. The 

fuel consumption of a motor is always a serious 
question, and one of importance to the pur¬ 
chaser as well as to the manufacturer. 

Ordinarily about one and two-tenths pints of 
gasoline per horsepower hour under full load 
will cover the fuel consumption. That is, when 
the mixture is of the proper explosive quality 
and the water comes from the jacket at a tem¬ 
perature of about 160 degrees Fahrenheit. 

The temperature of the water in the jacket 
around the cylinder has a great deal to do with 
the fuel consumption. 

If the water is forced around the cylinder so 
as to keep it cold, the heat from the combustion 
is cooled down so quickly by radiation that the 
expansive force of the burning gases is mate¬ 
rially reduced, and consequently less power is 
given up by the motor. 

The object of the water is not to keep the cyl¬ 
inder cold, but simply cool enough to prevent 


The Automobile Handbook 


333 


the lubricating oil from burning. The hotter 
the cylinder with effective lubrication the more 
power the motor will develop. 

It should be remembered that a hot motor is 
the most economical in fuel. 

Gasoline, Thermo-dynamic Properties of 
Gasoline and Air. The following table, 11, 
gives the thermo-dynamic properties of gaso¬ 
line and air, and may be of interest, in view of 
the fact that information on this subject is 
sparse, and most of that only theoretical, or 
empirical deductions. 

This table gives the explosive force in pounds 
per square inch of mixtures of gasoline vapor 
and air, varying from 1 to 13 down to 1 to 4, 
also the lapse of time between the point of igni¬ 
tion and the highest pressure in pounds per 
square inch attained by the expanding charge 
of mixture. The tests from which the results 
given were obtained, were made with a charge 
of mixture at atmospheric pressure, so as to 
more accurately note the results, as the mixture 
takes much longer after ignition to attain its 
highest pressure, and is slower also in expand¬ 
ing. 

It may be well to remember that there are no 
more heat-units, and consequently no more foot¬ 
pounds of work in a mixture of gasoline and air, 
under 5 atmospheres compression, than under 
1 atmosphere compression. 

Flanged or ribbed air-cooled motors will ap¬ 
proach the figures given in the table for the 


334 


The Automobile Handbook 


initial explosive force for the varying compres¬ 
sions, very closely, while thermal-siphon wa¬ 
ter-cooled motors will come within about 20 
per cent of these results, and pump and radiat¬ 
ing coil cooled motors will come within about 
30 per cent. While it appears at the first glance 
that the proper thing to do to get the greatest 
efficiency from a motor would be to let it run 
as hot as possible, experience has shown that 
the repair bill of a hot motor will more than 
offset its efficiency over the cooler water-jack¬ 
eted motor, with pump and radiating coils. The 
last two columns in the table give the tempera¬ 
ture of the burning gases, the first of the two 
columns the actual temperature with the ac¬ 
companying mixture of gasoline and air, and 
the second the theoretical temperatures, or tem¬ 
perature to which the burning mixture should 
attain, if there were no heat losses. 

TABLE 11. 


THERMO-DYNAMIC PROPERTIES OF GASOLINE AND AIR. 


Gasoline, 
Vapor and 
Air. 

Time in 
Seconds 
between 
Ignition 
and 

Highest 

Pres 

sure.* 

Explosive Force in 
Pounds per sq. in. 


Temperature 
of Combustion 
in Degrees 
Fahrenheit.* 

Compression 
in Atmospheres. 

3 

4 5 

Actual. 

Theo¬ 

retical. 

1 to 13 

1 to 11 

1 to 9 

1 to 7 

1 to 5 

1 to 4 

0.28 

0.18 

0.13 

0.07 

0.05 

0.07 

156 

183 

234 

261 

270 

240 

208 | 260 
244 | 305 
312 ] 390 
348 I 435 
360 | 450 
320 1 400 


1857 

2196 

2803 

3119 

3226 

2965 

3542 

4010 

4806 

6001 

6854 

5517 


*At atmospheric pressure. 


























The Automobile Handbook 


335 


Gear—Changing. In changing gears the au- 
toist should endeavor to have the motor and 
car moving at nearly corresponding rates of 
speed before the clutch is engaged. With the 
planetary type of gear, changing is simple, and 
drivers usually guess at the proper period at 
which to make the change, any mistake in esti¬ 
mating the rates of the car and motor being of 
little consequence, as the bands will slip instead 
of transmitting the shock to the gear. A simi¬ 
lar action occurs in the case of individual 
clutch or friction gears, but with the sliding 
type severe strains and shocks have to be taken 
up by the clutch, and are usually transmitted in 
part to the gear if the clutch is not slipped. 
What applies to the sliding type in general ap¬ 
plies to the other types as well. 

In changing from a lower to a higher gear it 
will be necessary to speed up the motor by 
means of the throttle or accelerator in order to 
store enough energy in the flywheel to furnish 
the work needed to accelerate the car to its 
new speed. As the speed of the car increases 
the higher gear should be engaged, the autoist 
not being in too great a hurry to make the 
change. The movement of the change gear le¬ 
ver should be made quickly in order that the 
car does not lose way. When changing from a 
higher to a lower gear the change should be 
made as quickly as possible before the car has 
time to slow down. When climbing a steep hill 
it should be ascended as far as possible on the 




336 


The Automobile Handbook 


high gear by proper use of the throttle and 
spark, and the change down to the lower gear 
made as soon as the motor begins to labor or is 
in danger of stopping. The presence of an 
unusual number of passengers in the car will 
affect its ability to negotiate grades which ordi¬ 
narily are taken on the high gear, and the auto- 
ist should remember this and not attempt to 
force the car to travel on that gear with the in¬ 
creased load, but resort to a lower gear. 

Gear Case and Rear Axle. It is a familiar 
fact that the gear case requires to be periodic¬ 
ally emptied of oil, and the accumulated metal 
grit washed out before fresh oil is supplied. The 
same is true of the rear live axle casing, except 
that the gears in the axle do not clash and 
therefore do not wear out as fast as the change 
speed gears. At least once in a season the oil 
in the rear axle should be drained out, a liberal 
supply of kerosene introduced, and the axle 
jacked up while the engine is run to agitate the 
oil and wash out the differential, etc. 

Gears, Diametrical Pitch System of. Table 
12 gives the necessary dimensions for lay¬ 
ing out and cutting involute tooth spur gears 
from No. 16 to No. 1 diametral pitch. Formulas 
are also given so that if the number of teeth 
and the diametral pitch are known, the pitch 
diameter can be ascertained—also, the diam¬ 
etral pitch, outside diameter, number of teeth, 
working depth, and clearance at bottom of 
tooth: 


The Automobile Handbook 


337 


P = Pitch diameter in inches. 

D = Diametral pitch. 

W = Working depth of tooth in inches. 

T = Thickness of tooth in inches. 

O — Outside diameter in inches. 

C = Circular pitch in inches. 

T 

(1) Pitch diameter=— 

D 

2 

(2) Outside diameter=P-{- 

D 

T 

(3) Diametral pitch=— 

P 

3.142 

(4) Circular pitch—- 

D 

2 

(5) Working depth of tooth——=2-^D 

D 

(6) Number of teeth=PXO 

(7) Thickness of tooth—1.571XD 

C 

(8) Clearance at bottom of tooth=— 

20 

For example: Required, the pitch diameter 
f a gear with 20 teeth and No. 5 diahaetral 



338 


The Automobile Handbook 


pitch. From Formula No. 1, as the pitch diam¬ 
eter is equal to the number of teeth divided by 
the diametral pitch, then 20 divided by 5 
equals 4, as the required pitch diameter in 
inches. 

What is the outside diameter of the same 
gear? From Formla No. 2, as the pitch diam¬ 
eter is 4 inches, and the diametral pitch No. 
5, then 4 plus 2/5 equals 4 2/5 as the proper 
outside diameter for the gear. 

What would be the diametral pitch of a 
gear with 30 teeth and 5 inches pitch diame¬ 
ter? From Formula No. 3, 30 divided by 5 
equals 6, as the diametral pitch to be used for 
the gear. In this manner by the use of the 
proper formula any desired dimension may be 
obtained. 


TABLE 12. 

DIMENSIONS OF INVOLUTE TOOTH SPUR GEARS. 


Diametral 

Pitch. 

Circular 

Pitch. 

Width of 
Tooth on 
Pitch 
Line. 

Working 
Depth of 
Tooth. 

| 

Actual 
Depth of 
Tooth, 

Clearance 
at Bottom 
of Tooth 

1 

3.142 

1.571 

2.000 

2.157 

0.157 

o 

1.571 

0.785 

1.000 

1.078 

0.078 

o 
* > 

1.047 

0.524 

0.607 

0.719 

0.052 

4 

0.785 

0.303 

0.500 

0.539 

0.039 

5 

0.628 

0.314 

0.400 

0.431 

0.031 

(i 

0.524 

0.202 

0.333 

0.360 

0.026 

7 

0.447 

0.224 

0 286 

0.308 

0.022 

8 

0.303 

0.100 

0.250 

0.270 

0.019 

10 

0.314 

0.157 

0.200 

0.216 

0.016 

12 

0.202 

0.131 

0.107 

0.180 

0.013 

14 

0.224 

0.112 

0.143 

0.154 

0 011 

10 

0.100 

0.008 

0.125 

0.135 

0.009 


Gears, Horsepower Transmitted by. The fol¬ 
lowing-formulas will give the horsepower that 


















The Automobile Handbook 


339 


may be transmitted by gears with cut teeth of 
involute form and of various metals. 

H.P = Horsepower. 

P — Pitch diameter in inches. 

C = Circular pitch in inches.* 

F = Width of face in inches. 

R = Revolutions per minute. 

PXCXFXR 

H.P=-(Annealed tool steel.) (1) 

(Mach, steel or Phos¬ 
phor Bronze.) (2) 

(Cast Brass.) (3) 


(Cast Iron.) (4) 

Example: Required, the horsepower which 
a tool steel pinion, 2 inches pitch diameter, 1 
inch face and No. 10 diametral pitch, will 
transmit at 900 revolutions per minute. 

Answer: From the table the circular pitch 
corresponding to No. 10 diametral pitch is 

♦The circular pitch corresponding to any diametral pitch num¬ 
ber. may be found by dividing the constant 3.1416 by the diam¬ 
etral pitch. 

Example: What is the circular pitch in inches corresponding 
to No. 6 diametral pitch. 

Answer: The result of dividing 3.1416 by 6 gives 0.524 inches 
as the required circular pitch. 


90 

PXCXFXR 

H.P=—- 

140 

PXCXFXR 

H.P=- 

410 

PXCXFXR 

H.P=- 

550 







340 


The Automobile Handbook 


0.314. Then by Formula No. 1, 2X0.314X1X 
900 equals 565.2. This, divided by 90, gives 
5.29 horsepower. 

Gear, Internal-Epicyclic. It is often desired 
to ascertain the speed of rotation of the differ¬ 
ent members of this form of gearing. To cal¬ 
culate their speeds, the following formulas are 
given, which, by reference to the letters desig¬ 



nating the different parts in Figure 149, may be 
readily solved. 

Let R be the revolutions per minute of the 
disk or spider carrying the pinions D. 

Let N be revolutions per minute of the gear 
E. 

Let G be the revolutions per minute of the 
internal gear F. 

When the internal gear F is locked and gear 
E rotating, the speed in revolutions per minute 
of the disk or spider carrying the pinions D is 



The Automobile Handbook 


341 


E 

R — N - 

E + F 

If the internal gear be locked and the spider 
carrying the pinions D be rotated, then the 
speed in revolutions per minute for the gear E 
will be 

E + F 

N = R - 

E 

If the spider carrying the pinions D be held 
rigid and the gear E be rotated, the speed in 
revolutions per minute for the internal gear F is 

N X E 

G =- 

F 

If the pitch diameter of the gears is not read¬ 
ily obtainable, the number of teeth in each gear 
mav be used instead, as the result will be ex- 
actly the same. 

Generator. This term is usually applied to 

a nv form of chemical or mechanical device 

• 1 

which can be used to produce a current of elec¬ 
tricity. Mechanical generators of electricity 
used for ignition purposes are of two forms, 
dynamos or magnetos. The former is self-excit¬ 
ing by means of coils of w T ire wound upon the 
magnet limbs. The latter has permanent mag¬ 
nets instead of coils of wire to induce the cur¬ 
rent in the armature of the magneto. Mag- 





342 


The Automobile Handbook 


netos, on account of their simplicity of con¬ 
struction and low first cost, are more generally 
used for ignition purposes than dynamos. They 
may be operated by the motor with a friction- 
pulley, gear or belt. Figure 150 shows one form 
of a magneto arranged to be operated by the 
friction pulley on the left-hand end of the ar¬ 
mature shaft. 

The simplest form of magneto and the one 
shown in Figure 150 consists of two or more 

f ’ ■ ■ ■ ——— -“ —^ 



MAGNETO 


Fig. 150 

magnets of horse-shoe shape, the ends of which 
embrace the pole-pieces, between which rotates 
a shuttle armature wound with small insulated 
copper wire. Rotation of the armature of the 
magneto tends to disturb the path of the lines 
of force or magnetic flux flowing between the 
ends of the permanent magnets, which in turn 
set up powerful induced currents in the arma¬ 
ture. The current produced by the magneto is 
of an alternating nature, but is converted into a 








































The Automobile Handbook 


343 


direct or continuous current by means of the 
commutator on the armature shaft. 

Generator—Gas. The gras used in gas lamps 
is generated by water, in minute quantities, 
dropping on acetylene (carbide of calcium) ; 
the gas thus formed passes from the generating 
chamber into the body of the lamp and is con¬ 
sumed at the lava tips, which are placed in 
front of a highly polished mirror. The genera¬ 
tors in some cases are separated from the lamp 
itself and placed on the dashboard, or under the 
hood, a rubber hose conveying the gas to the 
lamp. 

The interior of the carbide chamber or bas¬ 
ket being more or less in contact with the water 
distribution apparatus, the parts of both appa¬ 
ratus are liable to clogging by the formation of 
lime residue in the generation of gas. If this 
residue is allowed to collect, it will have to be 
removed with a chisel, which is a ticklish opera¬ 
tion in a light construction like that of a gen¬ 
erator, especially around the water valve or 
its outlet. Acids are sometimes used to remove 
the deposit, but as they eat the metal, their use 
should be prohibited. The basket and pot 
should be thoroughly washed out after each run 
with .water, the water outlets being cleaned 
with special brushes, when these are obtaina¬ 
ble, or by wires, removing all traces of lime. 
The water valve should be scraped and tested 
to see whether it seats properly, care being 
taken not to damage the valve or its seat in so 


344 


The Automobile Handbook 


doing. While the valve is dismounted for clean¬ 
ing it would be well to see that its stem is 
straight, and that it works with some ease in the 
threaded portion attached to the water chamber. 
The gas valves should be cleaned and should 
seat snugly, so that there will be no leakage 
past them. This applies also to the gas valves 
on the lamps. 

The best position for the generator is on the 
running-board just back of the change-gear 
quadrant, and sufficiently far out from the 
frame to allow a free circulation of air all 
around it. The generator will keep cool in this 
position and will perform its work to the best 
advantage when properly cooled. 

Governor, Use of. All explosive motors when 
running under a heavy load, slow down, or re¬ 
duce their speed very materially. If the load 
be entirely or partially removed from the mo¬ 
tor very suddenly, it will tend to race. This 
racing, which causes excessive wear and vibra¬ 
tion, is very injurious to the motor. On light 
cars with small-powered motors, racing is 
usually prevented by some form of hand con¬ 
trol, such as retarding the ignition or throttling 
the mixture supply. On heavy, high-powered 
automobiles, racing of the motor is eliminated 
by the use of some form of centrifugal gov¬ 
ernor, which controls the motor-speed by one of 
the three following methods: Retarding the 
ignition—Throttling the supply of mixture— 
Preventing the exhaust-valve from opening. 


The Automobile Handbook 


345 


Figure 151 shows a form of governor which 
operates by preventing the exhaust-valve from 
opening. When the speed of the motor passes 
its normal limit, the balls A of the governor 
move out towards the periphery of the gear or 
wheel which carries them, causing the earn B 
to be moved to the right by the action of the 
dogs on the governor arms, which engage in a 
grooved collar on the sleeve C. 



The nose of the cam B is thus kept out of 
engagement with the roller D until the motor 
resumes its normal speed, thus preventing the 
valve-lifter from opening the valve. 

Normally the cam is held in positon by the 
springs attached to the governor balls, against 
the shoulder of the bearing F, which carries the 
cam-shaft G. 

On some types of cars the “hydraulic” type 


































346 


The Automobile Handbook 


of governor is used. The Packard car, for in¬ 
stance, uses this type. It consists of a circular 
chamber divided in the middle by a flexible dia¬ 
phragm, one side being filled with water and 
connected with the pump and with the cylin¬ 
ders. On the side of the diaphragm, opposite 
the water, is a large piston, the stem of which 
projects through the guide and bearing, and is 
connected with the throttle. As the motor is 
speeded up, the velocity of the water from the 


TABLE 13 . 

HORSEPOWER REQUIRED TO MOVE A VEHICLE WEIGHING 

1,000 POUNDS. 



5 

6 
8 

10 

12 

14 

16 

18 

20 


1.3 

1.7 

2.1 

2.6 

3.0 

3.4 

3.8 

4.3 

4.8 

5.2 

5.6 

6.0 

6.5 

1.4 

1.9 

2.4 

2.9 

3.3 

13.8 

4.3 

4 8 

5.3 

5.8 

6.3 

6.7 

7.2 

1.8 

2.3 

2.9 

3.5 

4.1 

4.7 

5.3 

5.8 

6.4 

7.0 

7.6 

8.2 

8.7 

2.1 

2.7 

3.5 

4.2 

4.8 

5.5 

6.2 

6.9 

7.6 

8.4 

9.0 

9.6 

10.4 

2.4 

3.2 

4.0 

4.8 

5.6 

6.4 

7.2 

8.0 

8.8 

9.6 

10.4 

11.2 

12.0 

2.8 

3.6 

4.5 

5.4 

6.3 

7.2 

8.1 

9.0 

10.0 

10.8 

11.7 

12 6 

13.5 

3.1 

4.1 

5.0 

6.1 

7.1 

8.1 

9.1 

10.1 

11.1 

12.3 

13.1 

14.1 

15.1 

3.4 

4.5 

5.5 

6.7 

7.8 

9.0 

10.1 

11.0 

12.1 

13.5 

14.5 

15.6 

16.5 

3.7 

4.9 

6.1 

7.4 

8.6 

9.8 

11.1 

12 2 

13.5 

14.8 

15.9 

17.2 

18.3 


pump is increased and this acts against the dia¬ 
phragm, moving the piston and tending to close 
the throttle. As the motor speed decreases the 
water pressure is lessened and the throttle tends 
to open. 

If left to itself, the Packard governor will 
hold the motor very closely and uniformly to 
any speed for which the throttle may be set by 
the sector lever on the steering wheel. 

Grades—Power Required to Climb. Table 13 































The Automobile Handbook 


347 


gives the approximate horsepower required to 
move a vehicle with a total load of 1,000 pounds, 
at varying speeds. 

Graphite for Cylinder Lubrication. Flake 

graphite has been used as a lubricant for cylin¬ 
ders of gasoline engines in many cases. It 
could be used in the proportion of a scant tea¬ 
spoonful to a pint of oil. This mixture may be 
introduced into the crankcase by removing the 
side plate or by pouring it down the vent tube. 
Some users introduce the graphite direct to the 
cylinders through the sparkplug hole, or the 
opening for the make-and-break parts, using an 
insect gun quill with rubber tube attached. 
When the latter method is used the quill is 
filled by inserting it into the graphite, followed 
by blowing through the rubber tube, when the 
graphite will be discharged into the cylinder. 

In every case the accumulation of too much 
graphite on the plugs should be prevented, but 
a small amount does little, if any harm, espe- 
ciallv if there are gas currents that will clean 
it off. On anv engine lubricated with ordinary 
oil, which will run for a long time without soot¬ 
ing its plugs, graphite may be used to advant¬ 
age, and the plugs will soot little if any quicker. 

Heat of Combustion. The quantity of heat 
generated by the complete combustion of vari¬ 
ous gases and petroleum products is known 
as the heat value of the fuel, and represents the 
maximum amount of heat that can be obtained 
from a given quantity of the fuel. No accurate 


348 


The Automobile Handbook 


rule lias yet been devised by which to compute 
the heat value of any chemical compound from 
its formula and the heat values of the elements 
of which it is composed. Hence, the heat values 
of compounds must be found by a separate de¬ 
termination for each one in the laboratory. The 
heat developed by the combustion of some of 
the commoner fuels and gases is given in Table 
14. In the case of carbon, the heat developed 
by its complete combustion, forming CO.,, and 
the heat of its partial combustion to CO. are 
given; also the heat of combustion of CO to 
C0 2 . 

Heat Value of a Mixture. The heat value 
of a mixture may be found from the heat val¬ 
ues of the substances of which it is composed 
and the percentage of each substance. If h 1? 
h 2 , h.., etc., represent the heat values of the 
substances forming the mixture, and p lt p.,, p 3 , 
etc. represent the percentage of each substance, 
the heat value of the mixture will be repre¬ 
sented by the following formula: 

hm^rpjhj-f-p 2 h 2 +Poh 3 -f etc. 

Example.—A certain gas has the following 
composition : 


Constituents of Gas Per Cent. 

Hydrogen, II . 20 

Marsh gas, CII 4 . 70 

Acetylene, C 2 H 2 . 10 


What is the heat value per cubic foot of the 
mixture ? 

Solution.—Referring to Table 14, the heat 





TABLE 14. 

MIXTURES OF AIR AND GASES, AND RESULTING HEAT OF COMBUSTION. 


Fuel 


Oxygen, O . 

Nitrogen, N. 

Hydrogen, H. 

Carbon, C. 

Carbon, C . 

Carbon monoxide, CO. 

Carbon dioxide, C0 2 . 

Methane (marsh gas), CH 4 . . 
Ethylene (olefiant gas), Call* 

Ethane, C 2 H 6 . 

Benzol vapors, C 6 H 6 . 

Acetylene, C 2 H 2 . 


Chemical Proportions. 


23 lb.O + 77 lb.N = 100 lb. air 

21 vol.O + 79 vol.N = 100 vol. air 
2H + O = HoO 
C + O = CO 
C + 20 = C0 2 
CO + o = co 2 

1 lb.C4-2.66 lb.O = 3.66 lb.C0 2 
CPL + 40 = 2H a O 4- C0 2 
C 2 H 4 4 - 60 = 2H a O 4- 2CO a 
CoH 8 4- 70 = 3HoO + 2C0 2 
C 6 II 6 + 150 = 3HoO 4- 6 CO 0 
C 2 H 2 4- 50 = HoO 4- 2C0 2 “_ 


Weight 
of Gas 
at 30°, 
per 
Cubic 
Foot 

Pound 

Volume of 

1 Pound of Gas 
at Atmospheric 
Pressure 

Cubic Feet 

Volume 
Required 
to Burn 1 
Cubic Foot 
of Gas 

Cubic Feet 

Weight 
Required to 
Burn 1 
Pound of 

Gas 

Pounds 

Specific 
Heat of 
Gas at 
Constant 
Pressure 

Heat of 
Combustion 

B. T. U. 

per 
Pound 
of Fuel 

B. T. U. 

per 
Cubic 
Foot of 
Gas at 
62* 

32° 

62« 

0 

Air 

O 

Air 

.08927 

.07847 

.00562 

11.20 

12.77 

178.80 

11.88 

13.55 

189.80 

• • • 

• • • 

.5 

• • • 

• • • 

.5 

• • • 

2.0 

3.0 

3.5 

7.5 

2.5 


8.66 

".57 
• • • • 

4.00 

3.43 

• • • • 

• • • • 

• • • • 


.21751 

.24380 

3.40900 







2.38 

34.80 

62,000 

4,400 

14,600 

4,385 

23,976 

21,476 

22,356 

18,183 

21,421 

327 








.07704 

.12323 

.04538 

.07830 

.08369 

.22363 

.07251 

12.77 
8.12 
22.37 
12 77 
11.94 
4.47 
13.79 

13 55 
8.60 
23.73 
13.55 
12.67 
4.74 
14.63 

2.38 

2.48 

.24790 

.21700 

.59290 

.40400 

.37540 

324 

9.52 

14.28 

16.66 

35.7 

11.9 

17.40 

14.90 

• • • • * 

• • • • • 

1,010 

1,585 

1,765 

3,836 

1,464 















































































































[a t t 

Qyj. -s«SAO ax* « A *.> 'e >3 


■I 










miesth >•(011 UoIckm?;) 

















































The Automobile Handbook 349 

values per cubic foot of these gases are seen to 
be 327, 1,010 and 1,464 B. T. U., respectively. 
Apply the formula just given. p x = .20, p 2 ' = 
.70, and p 3 = .10. Also, h, = 327, h 2 = 1,010, 
and h 3 = 1,464. Substituting, hm — .20 X 327 
+ A0 X 1,010 + .10 X 1,464 = 65.4 + 707 + 
146.4 = 918.8 B. T. U. Ans. 

Temperature of Combustion. The theoret¬ 
ical temperature of the combustion of a given 
filel can easily be calculated. Making no al¬ 
lowance for losses of heat, and supposing that 
just enough air is furnished for the combustion, 
burning carbon should have a temperature 
about 4,940° above zero; while burning hydro- 
gem should have a temperature about 5,800° 
above zero. In practice, these temperatures 
are never attained, on account of heat losses. 

Loss of Heat. The loss of heat from any hot 
object is accomplished in three ways: by con¬ 
vection, by conduction and by radiation. In 
all practical cases a body loses heat by a com¬ 
bination of these processes. 

When heat is produced in the cylinder by the 
combustion of the gases, the piston is at or near 
the upper dead center; that is, it remains nearly 
stationary when the heat is greatest and when 
the heat loss per unit area of inclosing walls is 
most rapid. 

Under the usual conditions of ignition, the 
gas contained in the cylinder must be set into 
violent motion by the spread of the flame 
through it, and this motion will aid the dissipa- 


350 


The Automobile Handbook 


tion of the heat in the gas to the containing 
walls. So convection will be an important fac¬ 
tor in the process and perhaps the principal 
factor. Perhaps a part of the gain in power 
which has resulted, in some instances, from the 
use of multiple ignition may be due to violent 
motion of the gas. Practically all air cooled 
motors have their valves in the head, so the 



Fig. 152 


charge is contained between the cylinder walls 
and the piston head. 

The heat absorbed by the water-jacket is 
equal to the weight of water passed through the 
jacket multiplied by the temperature range; or, 
in other words, it is the difference between the 
temperature of the water when it enters the 
water-jacket and that of the water when it 
leaves the jacket. For instance, if the tempera¬ 
ture of the entering water is 50° and that of 
escaping water is 180°, the temperature range 


















































The Automobile Handbook 


351 


is 180° — 50° — 130°. Then, if the weight of 
the water passing through the jacket in 1 hour 
is 100 pounds, the heat carried away is 100 X 
130 = 13,000 British thermal units. 

Horizontal Engines. Fig. 152 shows a view, 
and Fig. 153 a longitudinal section of a hori¬ 
zontal two cylinder opposed motor. Referring 
to Fig. 152, the cylinders a, a, are bolted to a 
common crank case b, on the cover of which is 
mounted a mechanical lubricator c, for lubri- 
eating the pistons and bearings. Connection 
between carbureter d, in which the fuel is va¬ 
porized, and the inlet valve chambers of the 
two cylinders is made by the supply pipe e. The 
charge is ignited by the spark plugs f, f, the 
time of the spark being controlled by means of 
the timer g. The cooling-water connections to 
both cylinders are made at h, h. 

Reference to the sectional view, Fig. 153, 
shows how the cylinders a are arranged with 
reference to each other and to the crankcase b, 
the offset in the cylinders necessitating an off¬ 
set in the connecting rods c, which are attached 
to cranks 180°. apart. By thus setting the cranks 
and arranging the cylinders in opposition, the 
crankshaft d receives a power impulse at each 
revolution, with no gap or uneven interval in 
the time of the impulse. The explosive mixture 
enters the cylinders through automatic inlet 
valves e, the burned gases passing out through 
the exhaust valves f mechanically operated by 
means of' the two-to-one gears g and h, the 


;i52 


The Auto-mobile Handbook 



153 






































































































































































The Automobile Handbook 


353 


shaft on which the latter is mounted carrying 
the exhaust-valve cam i, against which presses 
the roller of the exhaust-valve push rod j. Com¬ 
pression relief cocks k, mounted in a bushing 
that passes through the cylinder water-jackets 
1, are provided for relieving the compression 
pressure in starting. 

Horsepower of Explosive Motors. The first 
requisite is to find the number of power strokes 
made per minute by the motor. In a single 
cylinder motor of the four-cycle type there is 
one power stroke for every two revolutions, 
and if the motor has four cylinders there is 
one power stroke for every revolution of the 
crank shaft. The number of power strokes then 
may be found by the following formula (refer¬ 
ring to a four-cycle motor) : 

C 

N = —XS 

4 

in whidh N = Number of power strokes per 
minute. 

C = Number of cylinders. 

S = Angular velocity of crank shaft in rev¬ 
olutions per minute. 

Having ascertained the number of power 
strokes per miute, the horsepower is found by 
the formula, 

P L A N 

H.P =- 

33,000 

in which H.P = Horsepower. 



354 


The Automobile Handbook 


P = Mean effective pressure (M. E. P.). 

L = Length of stroke in feet. 

A = Area of piston in sq. in. 

N = Number of power strokes per minute. 
This formula does not discriminate between 
mechanical friction and losses in “fluid” fric¬ 
tion. A formula that is more arbitrary and 
that fits the majority of cases, requiring only 
the use of a few facts, such as diameter of cyl¬ 
inder, length of stroke, and revolutions per min¬ 
ute, is presented as follows: 

VXN 

H.P =- 

10,000 

in which 

Y = volume of cylinder in cu. inches. 

N = number of power strokes per min. 

The constant used varies from 9,000 to 14,000 
depending upon certain types of engines; 10,000 
being an average figure for four cycle engines. 
The brake horsepower will be from 65 to 85 per 
cent of the result obtained; 80 per cent may be 
taken as an average. As an example we may 
take a four-cycle, four-cylinder motor 4%-in. 
bore and 4 1 /2-im stroke making 1,200 power 
strokes per minute. Volume (Y) of cylinder 
equals area of piston 15.9 sq. in. X length of 
stroke 4 1 /2=71.55 cu. in., and multiplying this 
by 1,200 (N) and dividing the product by 10,- 
000 gives 8.05 H.P. Taking 80 per cent of this 
as the brake horsepower the result is 6.44 H.P. 



The Automobile Handbook 


355 


From a. theoretical standpoint a two-cycle ex¬ 
plosive motor should not only have as great a 
speed, but also be capable of developing almost 
twice the power that a four-cycle motor does. 
It is a fact nevertheless that its actual perform¬ 
ance is far different. 

The horsepower of a two-cycle motor may be 
calculated from the following formula, 


in which 


D 2 XSXN 

H.P=- 

21,000 


D=diameter of cylinder in inches. 

S=stroke of piston in inches. 

N=number of revs, per minute. 

Example: Required, the horsepower of a two- 
cycle motor of 4V2 inches bore and stroke, with 
a speed of 900 revolutions per minute. 

Answer: The square of the bore multiplied 
by the stroke is equal to 91.125, which multi¬ 
plied by 900, and divided by 21,000, gives 3.91 
as the required horsepower. The results given 
by the above examples agree very closely with 
those obtained from actual practice. 

Hub—Floating Type. Fig. 154 shows a full¬ 
floating type of live rear axle in which the bear¬ 
ings are of the annular type, and the driving 
jaws at the ends of the shafts engage with the 
hub in a proper manner to abort failure from 
lost motion. 



356 


The Automobile Handbook 


In this case the tube is reduced in diameter 
to take the bearings, and the shoulder so 
formed is taken advantage of in the process of 
providing for thrust. The shaft has no work to 
do excepting to take torsional moments, and 



the design throughout includes drop forgings 
of steel and drawn-steel parts. The inner race 
of the ball bearings is a sufficiently heavy tube, 
but it is not shaped in such a way as to act as a 
“preventer bearing,’' hence complete depend¬ 
ence is placed on the ball bearings and they are 






































































































The Automobile Handbook 


357 


made large enough to take the responsibility. 
This class of hub work is much in evidence in 
various makes of cars, and this particular ex¬ 
ample is from the 1910 McCord car. 

Hub Cap Loose. A hub cap, particularly of 
a plain bearing car whose hubs are greased in¬ 
stead of oiled, will unscrew rather easily if its 
threads are a loose fit. This is particularly the 



Fig. 155 

Illustrates Locking Loose Hub Caj>s 


case with the right-hand hub caps, since the vis¬ 
cosity of the grease results in a constant effort 
to unscrew them. As good a way as any to lock 
the cap is to chip the notch, A, Fig. 155, in the 
flange of the bronze bushing in the hub, and to 
arrange a set screw in the cap to enter this 
notch. If the set screw is of the ordinary har¬ 
dened sort and holds only by its own pressure, 
it is liable to shake loose some time or other. 












































358 


The Automobile Handbook 


I 


A better plan is to use a button head V±-20 screw 
of ordinary steel, running the threads clear up 
to the head by means of a die. A notch is filed 
in the head of the screw, as shown at B, and the 
screw is cut off to such a length that the head 
will bottom oh the cap when the end of the 
screw enters the notch A, then a burr is raised 
at B in the brass of the cap with a prick punch; 
thus the screw is secured against turning until 
it is wanted to do so. The same expedient 
is useful in many other places where it is de¬ 
sired to keep a screw from loosening. 

Modern Hub Practice. The trend is in the 
direction of ball and roller bearings for wheels, 
the hubs being accurately machined from steel 
castings, or die forgings. Hub flanges are wide, 
and a suitable number of bolts of good diameter 
are used to bolt the woodwork into secure rela¬ 
tion. 

There is a decided tendency, also, to have the 
spokes at the mitre very accurately fitted, and 
fastened by glue, so that the wheel may be 
easily disassembled at any time, for any pur¬ 
pose, as for instance, a new hub might be sub¬ 
stituted at will for one that has been damaged 
in service. 

Hydraulic Clutch. Fig. 156 illustrates the 
principle upon which the hydraulic clutch 
works. The spider A is secured to the engine, 
shaft and carries two spur pinions B, B, which 

i 

are in constant mesh with the spur gear C, at¬ 
tached to the driven shaft. 


The Automobile Handbook 


359 


Spaces H, H, H, II are sections of a liquid 
tight casing, which is tilled with oil. 

The gears and oil spaces constitute a rotarv 
pump tending to circulate the surrounding oil. 
Several valves, one of which is shown at D, 



when opened, allow the free circulation of the 
oil through passages not shown, but when D is 
closed the oil is impounded, and practically no 
relative motion is possible between the pump 
members. When the valves are opened, and 


i 










































360 


The Automobile Handbook 


the oil is allowed to circulate freely, pinions B, 
B, on the engine simply run idly around the 
central gear C, and no torque is transmitted to 
the driven shaft, but when the oil valves are 
partially closed, the resistance between the 
pump members is increased and a driving ef¬ 
fort is communicated to gear C and the driven 
shaft. When the valves are fully closed, no rel¬ 
ative motion is permitted between the pump 
members, the result being that pinions B drive 
gear C and the driven shaft with only a slight 
amount of slip due to oil leakage. The clutch 
is operated by releasing a pedal, allowing spring 
F to act and bring the ring K into contact witbu 
the ball bearing heads of the oil valves D, which 
have previously been held, fully open by their 
springs. As the valves are more or less closed 
by the release of the pedal, the clutch torque 
increases, due to the action of the gear-pump, 
consequent upon the impounding of the oil, 
until finally they are entirely closed, when the 
driven shaft will then revolve at about 90 per 
cent of the engine speed. A still further mo¬ 
tion of the clutch causes engagement of the 
leather-faced conical surface G, thus locking 
the clutch to the engine shaft mechanicallv. 

The object of this device is to automatically 
insure an easy starting of the car, independent 
of the operator, and it is claimed that it serves 
much the same purpose as a change of gears in 
the starting operation, and that there is no 
serious heating of the oil under such conditions. 


The Automobile Handbook 


361 


Hydrogen Generator—Principle of. Hydro¬ 
gen when combined with oxygen makes a flame 
sufficiently hot to melt lead locally, and the 
burning process as it is applied to battery work 
becomes a reality. Oxygen is available in the 
air in sufficient quantity to allow of the use of 



the hydrogen flame, provided the latter element 
is available under slight pressure. To obtain 
hydrogen under slight pressure in sufficient 
quantity a hydrogen generator is used and is so 
contrived that the pressure is automatically lim¬ 
ited to that due to a few inches of water. Fig. 
157 illustrates the principle of construction at- 

















































362 


The Automobile Handbook 


tending sueli a generator, cut through the mid¬ 
dle, showing an outside shell S, the bottom of 
which is filled with zinc. From the top a two- 
compartment container H is inserted, with 
means for rendering the same tight around the 
seam at the top. The upper compartment A is 
filled with dilute sulphuric acid, and by means 
of the needle valve N the sulphuric acid is al¬ 
lowed to drip into the lower compartment B 
until it rises to the top of the connecting tube, 
above the line of the drip tube T from the up¬ 
per compartment and passes below. When the 
sulphuric acid passes down through the tube T 
and contacts with the zinc in the bottom chem¬ 
ical action is set up with a reaction as follows: 

FS0 4 -f Zn = Zn S 0 4 + H 2 

The middle chamber C acts as a seal and 
when the pressure of hydrogen equals the pres¬ 
sure of the column of dilute sulphuric acid the 
action terminates because no more sulphuric 
acid will flow until the hydrogen-gas pressure 
is decreased, as it will be if the hydrogen is con¬ 
sumed. In practice the process is continuous 
and automatic, thus enabling the operator to 
burn the lead joints as rapidly as they can be 
made up. 

Fig. 158 illustrates a form of generator that 
accords with practice, the principle being the 
same as that shown in Fig. 157, with the differ¬ 
ences in detail as follows: The receptacle A for 
sulphuric acid may be of any convenient shape, 


The Automobile Handbook 


363 


but it must be tight. The pipe P leads to the 
tank B, which is provided with a large hand 
hole Iv to use in passing the zinc to the inside 
and in cleaning out as occasion requires. Sul¬ 
phuric acid poured into B contacts with the 
zinc and hydrogen gas is formed. The pressure 



will be equal to the effective head of the col¬ 
umn of sulphuric acid, the excess acid is forced 
up into the receptacle A, and the formation of 
gas is interrupted, due to the uncovering of the 
zinc when the liquid passes up into A. The hy¬ 
drogen gas passes on to the burner through the 


















































364 


The Automobile Handbook 


filter-safety S. This water trap, acting as a 
safety, not only scrubs the gas but it prevents 
air from passing into the generator and in this 
way safety is assured. 

Fig. 159 shows details of the process after the 
Joints are made up, following the work of 
scraping the necks of the plates, and the sur¬ 



faces of the strap, in order to obtain a clean, 
bright metal-to-metal contact. 

Under no circumstances will lead run to¬ 
gether unless the surfaces are clean and bright; 
they must not stand for any length of time after 
scraping, because a coating of sulphate of lead 
will form over the scraped surfaces and the 
process of burning will be defeated. 


















































The Automobile Handbook 


365 


Ignition. In order that an explosive motor 
may operate economically, and with the highest 
percentage of efficiency, it is absolutely neces¬ 
sary that two objects shall be attained, viz.: A 
correct mixture of the gasoline and air, and that 
this mixture be correctly ignited at the proper 
time. 

Ignition of the explosive mixture is accom¬ 
plished by two methods, the electric spark and 
the incandescent tube; the latter system, how¬ 
ever, is falling rapidly into disuse. 

Electric Ignition. This form of ignition is 
in general use, two methods being employed, as 
follows: 

(a) Primary electric ignition, and (b) sec¬ 
ondary electric ignition. 

In the common parlance, these are called low 
tension and high tension, the former being given 
the additional name of the make-and-break sys¬ 
tem, while the latter is more often called the 
jump-spark system. The latter is, moreover, 
subdivided again according to the source of 
current, although for sparking purposes, all 
sources are alike. These are: 

(a-1) Dry cells. 

(a-2) Storage batteries. 

(a-3) Magnetos or generators. 

(a-4) Small dynamos and other sources of 
current. 

There are two methods of producing an elec¬ 
tric spark for ignition purposes: The first, by 
means of an induction coil which has only a 


366 


The Automobile Handbook 


single winding, composed of a few layers of in¬ 
sulated copper wire of large size, wound upon 
a bundle of soft iron wires, known as the core. 
The second, by the use of an induction coil with 
a double winding upon its core. The inner 
winding being composed of a few layers of in¬ 
sulated wire of large size, as in the coil just de¬ 
scribed, and an outer winding consisting of a 
great many layers of very small insulated cop¬ 
per wire, in fact, several thousand feet in 
length. 

The coil first described is known as a primary 
spark coil, from the fact that the spark or arc 
is produced by the direct effect of the battery 
or generator current flowing in the coil. This 
form of spark will not arc or jump across a 
space between two points, but simply occurs 
between the contact points on the breaking of 
the contact. 

The second form of induction coil is com¬ 
monly known as a secondary spark coil, because 
the arc or spark is produced in the secondary 
winding of the coil, and will jump or arc across 
a space between two fixed points, without the 
points first coming in contact. 

Induction Coil. Induction is the process by 
which a body having electrical or magnetic 
properties calls forth similar properties in a 
neighboring body without direct contact. This 
property is known as self-induction, and is 
caused by the reaction of different parts of the 
same circuit upon one another, due to varia- 


The Automobile Handbook 


367 


tions in distance or current strength. The cur¬ 
rent produced by an induction coil has a very 
high electro-motive force, and hence great 
power of overcoming resistance. 

The average user of an automobile is well 
aware that without the battery and the spark 
coil the motor would not operate. He has 
learned that, when the spark fails, there are 
certain forms to be gone through to ascertain 
the cause of trouble, but as there are other diffi- 


( 

V 


-n- 


-r-r 




\ 

) 


■-—*- 

SWITCH ~ + BATTER* 


iL 




-r-t- 


’ X 


f ■ +- ■'■■■■ 7 f '' 

# « 4 * i * « 

t *-./ > 

"----^ 

SWITCH ♦ -BATTERY 
INDUCTION COIL 


Fig. 160 


culties, it is desirable that more should be known 
of this important subject. 

If a current of electricty be caused to flow 
through a straight conductor forming a part of 
a closed electric circuit, lines of force, com¬ 
monly called magnetic whirls or waves, are in¬ 
duced in the air and rotate around the conduc¬ 
tor. 

If the current of electricity be flowing in the 
circuit and through the straight conductor from 








368 


The Automobile Handbook 


right to left, as shown in the upper view in Fig. 
160, the lines of force or magnetic whirls will 
rotate around the conductor from left to right, 
or in the direction of the hands of a clock. On 
the other hand, if the conditions be reversed 
and the current flows from left to right the lines 
of force or magnetic whirls will rotate from 
right to left, as shown in the lower view in Fig. 
160. The direction of rotation of these lines 
of force or magnetic whirls may be positively 
determined by the use of a galvanometer, an 
electric testing instrument having a needle simi¬ 
lar in appearance to that of an ordinary com¬ 
pass. Upon placing this instrument in the 
path of the lines of force and making and 
breaking the battery circuit by means of the 
switch, the needle of the galvanometer will be 
deflected from its zero point in the direction of 
the rotation of the lines of force. If the direc- 

i 

tion of the flow of the electric current through 
the circuit be changed by reversing the poles of 
the battery, the needle of the galvanometer will 
be deflected from its zero point in the opposite 
direction. Whether these lines of force or mag¬ 
netic whirls rotate continuously around the wire 
has not been demonstrated. They rotate with 
sufficient force to be tested by the galvanometer 
only until the electric current in the closed 
circuit has reached its maximum value after 
closing the circuit ; that is to say, only during 
the infinitesimal space of time required by the 
current to reach its full value or power. 


The Automobile Handbook 


369 


If, instead of a straight conductor, a loop of 
insulated wire, in the form of a circle, be until- 
ized for the passage of the current, as at A and 
B in Fig. 161, the lines of force will still rotate 
around the wire as shown, their direction being 
dependent on the direction of the electric cur¬ 
rent. If the electrical circuit be provided with 



Fig. 161 


a current reverser, or device for changing the 
battery connections in the circuit from positive 
to negative and vice versa, the lines of force can 
be made to rotate rapidly first in one direction 
and then in the other, as indicated in Fig. 160. 

Suppose this loop of insulated wire be com¬ 
posed of a great number of turns, it then be- 





























370 


The Automobile Handbook 


comes a coil or closed helix, and as all the lines 
of force cannot pass between the turns of the 
electrical conductor forming this helix they 
must pass completely through the helix instead 
of rotating around a single loop, as at A and B, 
Fig. 161. If the current flows through the con¬ 
ductor in the direction indicated by the ar¬ 
rows, at C in Fig. 161, and over and around the 
coil in the direction shown, the lines of force 
will flow through the coil towards the observer, 
and complete their path or circuit through the 
air, returning into the coil at the opposite end. 
If the current be reversed and flow around the 
coil in the direction of the hands of a clock, the 
lines of force will flow through the coil in the 
opposite direction, that is, away from the ob¬ 
server, as at D, Fig. 161. 

This form of coil or closed helix mav be-des- 

t/ 

ignated as the primitive form of an electro¬ 
magnet. When forming part of a closed elec¬ 
tric circuit it possesses the property of magnet¬ 
izing a bar of wrought iron placed within it. 
If a short round bar of wrought iron be placed 
a short distance within the coil, and the battery 
circuit be closed, the iron bar will, if the cur¬ 
rent is sufficiently strong, be sucked or drawn 
into the center of the coil, and a considerable 
effort will be required to withdraw it. 

The object of the bundle of soft iron Avires, 
Avhich form the core of any form of spark coil, 
is to increase the magnetic effect of the lines of 


The Automobile Handbook 


371 


force or magentic flux, or rather to reduce the 
resistance to their passage through the coil. 

As the resistance of air to the flow of the lines 
of force is about 100,000 times greater than that 
of wrought iron, the introduction of the iron 
core into the coil increases its magnetic effect 
enorntously. 

As has been previously stated, when a current 
of electricity flows through a conductor of wire 
forming a coil or closed helix, lines of force are 



induced and flow through, and also around the 
exterior of the coil. In a like manner, when the 
electric circuit is broken, the lines of force sud¬ 
denly reverse their direction, and travel through 
the coil with a tremendous velocity until they 
reach a state of neutralization. During this re¬ 
verse travel of the lines of force through the 
coil, a current of electricity is induced in the 
winding of the coil, but in the opposite direction 
to that in which the battery current was flowing. 
The effect of this induced current, which is of 
far greater intensity or pressure than the bat 

























































































































372 


The Automobile Handbook 


tery current which induced it, is to form an arc 
or spark at the breaking point in the circuit. 

Primary Spark Coil. Fig. 162 shows a ver¬ 
tical longitudinal section through an induction 
coil of the form first described, and known as 
a wipe or touch spark coil. It consists of two 
principal parts, a core, made of a bundle of 
soft iron wire, and a coil of wire around this 
core composed of from 3 to 5 layers of turns of 
insulated copper wire, varying in diameter from 
No. 16 to No. 12, B. & S. Gauge, according to 
the battery conditions under which the coil has 
ito operate. The iron core may vary from three- 
eighths of an inch in diameter and 6 inches long, 
to three-fourths of an inch in diameter and 12 
to 15 inches long, depending upon the intensity 
and capacity of the spark required. Reference 
to the drawing will show that the core A has 
upon its ends wood or fiber washers D. They 
may be square or round. Upon the portion of 
the core between the washers is a paper tube E, 
upon which the wire forming the primary wind¬ 
ing is wound. The ends of the wire forming the 
coil and shown at P are connected to the bind¬ 
ing posts or terminals indicated by the letter 
T, and located on top of the washers D. The 
wire B, forming the primary winding, is usually 
provided with an outer casing, as shown at C, 
to protect it from water and grease. 

The form of induction coil above described is 
generally used for ignition purposes on gas and 
gasoline motors fitted with a mechanical make 


The Automobile Handbook 


373 


and break form of spark, which is located with¬ 
in the combustion chamber of the motor itself. 

Secondary Spark Coil. Fig. 163 shows the 
secondary or jump-spark form of coil. It is 
composed of an iron core and a primary winding- 
similar to that described in conjunction with 
Fig. 162, with the addition of an outer winding 
of many turns of tine wire. This wire, of very 
small size, is known as the secondary winding, 
varying in diameter from No. 36 to No. 40 B. & 
S. Gauge, and in length from 5,000 to 10,000 
feet. In the drawing the induction coil is 
shown equipped with an electro-magnet make 
and break, or vibrator device, which is the form 
mostly used for ignition purposes. The other 
form, known as the plain jump-spark coil, has a 
mechanically operated make and break device 
attached to the motor to operate the coil. 

The arc or spark produced at the breaking 
point of the electrical circuit in which the pri¬ 
mary winding of the coil is connected is not 
utilized for ignition purposes in this type of coil. 
When the circuit is broken the sudden reaction 
or backward flow of the lines of force or mag¬ 
netic flux in the iron core produce an induced 
current in the secondary winding, but in the 
opposite direction to that of the battery cur¬ 
rent. This induced current is of so much 
greater intensity and velocity than that induced 
in the primary winding by this same reaction, 
that the arc or spark induced in the secondary 
winding of the coil will jump across a space 


374 


The Automobile Handbook 

































































































































































































































The Automobile Handbook 375 

from one end of the wire to the other, varying 
from inch to as much as 8 or 10 inches in 
length, dependent upon the length of wire in 
the secondary circuit, the electro-motive force 
of the battery and the frequency of the inter¬ 
ruptions or number of times per minute the 
electric circuit is made and broken. 

Referring to Fig. 163 A is the core, B the pri¬ 
mary winding and C the secondary. The two 
coils are held in place upon the core by the 
washers D. The primary wire B is wound over 
a paper tube E, and the secondary wire C is in¬ 
sulated from the primary wire by a mica insu¬ 
lating tube F. The coil proper is enclosed in a 
wood case G. 

The terminals or binding posts on top of the 
case G are connected with the ends of the sec¬ 
ondary wire 1 and 2. The secondary terminals 
are plainly indicated by the letter S'. In the 
ba se IT of the coil case is the condenser J, an 
essential feature of this form of coil, which 
utilizes the induced primary current to produce 
a greater reactive energy in the secondary 
winding. 

At the right-hand end of the coil and outside 
the casing G is located the electro-magnetic vi¬ 
brator or trembling device, which automatically 
makes and breaks the primary circuit. The 
end 3 of the primary wire is connected with the 
contact screw Iv through the bracket L. The 
spring M, carried by the bracket N, with screw 
0, is connected with the terminal or binding 


376 


The Automobile Handbook 


post P, immediately beneath it, by the wire 6 
through the bracket! N. The end 4 of the pri¬ 
mary wire is connected with another terminal 
or binding post P, at the other end of the base 
of the coil. The condenser J is connected 
across the contact points of the screw K and 
the spring M, by the wires 5 and 6 and screws 
Q and X. The condenser is composed of a num¬ 
ber of sheets of tinfoil Y, laid between sheets 
of specially insulated paper I, with the opposite 
end of every alternate sheet of tinfoil projecting 
from the paper insulation, as shown. These 
projecting ends are connected together, and by 
the wires 5 and 6 to the contact screw K and 
spring M, respectively, as previously described. 

When the coil is connected in, or forms part 
of a closed electric circuit by means of the ter¬ 
minal or binding posts P, on the base of the 
coil, the current flows through the primary 
winding B. This instantly produces a high de¬ 
gree of magnetism in the core A, and the pole- 
piece T of the core extension R becomes strongly 
magnetic and attracts the iron button W of the 
spring M. This draws the spring INI away from 
the end of the screw K, and in consequence 
breaks the electric circuit. This results in the 
demagnetizing of the pole-piece T and the con¬ 
sequent return of the spring M to its normal 
position in contact with the end of the screw K. 
So long as the electric circuit remains closed 
this operation is repeated at a very high rate 
of speed. The effect of this continuous opera- 


The Automobile Handbook 


377 


tion of the coil is to produce an intermittent 
current in the secondary winding of high inten¬ 
sity and velocity. If wires are placed in the 
holes in the small terminals or binding posts on 
the top of the coil and brought within a short 
distance of each other, a stream of sparks will 
pass from one wire to the other in a peculiar zig¬ 
zag manner and emit a loud, crackling noise, 
accompanied by a peculiar odor, caused by the 
formation of ozone through the electro-chemical 
action of the spark. 

Under ordinary circumstances the arc or 
spark which occurs on the breaking of the con¬ 
tact between the platinum points of the screw 
K and spring M would not be utilized, but by 
means of the condenser in the base, which is 
connected to these parts, as before described, 
the static charge of electricity generated by this 
action is stored in the condenser. When the 
contact is again made this stored electric energy 
is given np or discharged by the condenser and 
flows through the primary winding of the coil 
in connection and in the same direction as the 
battery current and increases the magnetic ef¬ 
fect of the core A enormously. 

When the coil is used in connection with a gas 
or gasoline motor a form of ignition device 
known as a spark plug is used. This is con¬ 
nected with the secondary terminals and 
screwed into the combustion chamber of the 
motor. A form of circuit breaker upon the 
motor is used to make and break the electric 


378 


The Automobile Handbook 


circuit at the desired point, and the resulting 
arc or spark inside the combustion chamber ig¬ 
nites the charge of vapor. 

This style of coil is sometimes used without 
the electro-magnetic vibrator, and a mechanical 
make and break device, actuated by the motor, 
is used instead, producing as a rule only a sin¬ 
gle spark. 

To remove any doubt as to the origin of the 
secondary or jump-spark form of induction coil, 
it may be here briefly stated, that it was in¬ 
vented by Rumkorff in the year 1851, long be¬ 
fore the inception of the automobile. 

Source of Current. As previously stated, 
there are several sources from which the electric 
current may be taken for ignition purposes, 
among which are dry cells, storage batteries, 
magnetos or generators, and small dynamos. 
Storage batteries will be treated upon later on. 
A few words regarding dry batteries, and mag¬ 
neto generators may not be out of place at this 
juncture. 

Dry Batteries are very generally used on 
moderate speed and low-priced cars. They are 
simple in construction, comparatively simple in 
operation, and their action is easy to under¬ 
stand. Each cell is composed of three elements: 
The carbon, the zinc, and the electrolyte. The 
carbon usually takes the form of a round stick 
placed in the center of a cylindrical vessel made 
of zinc in sheet form. The space between the 
carbon and the zinc is filled with the electrolvte 


The Automobile Handbook 


379 


generally a solution of sal-ammoniac, which is 
poured in on crushed coke. The top is closed, 
or rather sealed, with pitch to prevent the loss 
or evaporation of the liquid. Through this, 
project the ends of the carbon and the zinc, these 
being formed into binding posts for holding the 
wires. As this holding of the wires must be an 
intimate relation, the usual form is a threaded 
shank upon which a pair of nuts are mounted. 
Between these the wire to be connected is 
crushed or compressed by the moving together 
of the nuts. 

The two poles or binding posts are called the 
positive and the negative, and are indicated by 
the -j- sign for the former and the — sign for 
the latter. Carbon being the positive element, 
the 4- sign attaches to it. Now, the act of con¬ 
necting these terminals together so as to allow 
a flow of current allows of two different meth¬ 
ods of procedure, a right and a wrong way, it 
is true, but that was not what was meant. 

In one respect dry batteries have a decided 
advantage over storage batteries for ignition 
purposes, from the fact that on account of their 
high internal resistance they cannot be so 
quickly deteriorated by short circuiting. 

On account of this high internal resistance, 
dry batteries will not give so large a volume of 
current as storage batteries, but a set of dry 
batteries may be short circuited for five min¬ 
utes without apparent injury and will recuper¬ 
ate in from twenty to thirty minutes, while a 


380 


The Automobile Handbook 


storage battery would in all probability be 
ruined under the same conditions. 

If dry batteries only are used for ignition 
purposes, two sets should be carried, of not less 
than 6 cells each, connected with a two-point 
switch. One set of batteries should be used not 
to exceed thirty minutes and then the other set 
switched on. In this manner the batteries will 
have a much longer life than if used continu¬ 
ously. 

To ascertain the internal resistance of a dry 
or primary battery, proceed as follows: With a 
suitable voltmeter, obtain the voltage of the bat¬ 
tery at its terminals when on open circuit. 
With a known resistance in the battery circuit 
-—say 100 feet of No. 10 B. & S. Gauge copper 
wire—again obtain the voltage of the battery, 
also,note the amperage with an ammeter; this, 
however, must be done quickly before polariza¬ 
tion occurs. 

Let V be the voltage of the battery at its 
terminals when on open circuit, and v the volt¬ 
age of the battery with a known resistance in 
the circuit, let C- be the current in amperes 
flowing through the known resistance and R the 
required internal resistance of the dry or pri- 
mary battery, then 

V—V 

R=- 

C 

To demonstrate the truth of the above for- 



The Automobile Handbook 


381 


mula and also to prove the correctness of the 
instruments used in making the test, when the 
value of the internal resistance R has been as¬ 
certained, then C, the current flowing with a 
known resistance in the battery circuit, should 
equal in value the result of the formula given 
below, which is 

V—v 

C=- 

R 

Dry batteries which have become exhausted 
may in most cases be recuperated in the follow¬ 
ing manner: First disconnect the cells from each 
other and remove their pasteboard covers, then 
drill a hole in the sealing compound on top of 
the cell, about one-quarter of an inch in diam¬ 
eter and at least 2 inches in depth so as to in¬ 
sure getting below the sealing compound. Take 
1 ounce of bisulphate of mercury and put in a 
porcelain or earthenware vessel (on no account 
use a metal vessel) and pour over it one-lialf 
pint of boiling water—when cold, draw oft* the 
clear solution, being careful not to disturb the 
yellow precipitate left at the bottom of the ves¬ 
sel, which is useless and should be thrown away 
at once, as it is a rank poison. Dissolve 4 
ounces of sal-ammoniac in 1 pint of hot water, 
and when cold mix with the first solution and 
the recuperative agent is then ready for use. 
Take a small glass funnel, or a tin one that is 
thoroughly painted or enameled, and intro- 



382 


The Automobile Handbook 


duce about a tablespoonful of the liquid into 
each cell through the hole already drilled for 
this purpose. The liquid must be introduced 
into the cells very slowly, as it will take a long 
time to absorb, and the cells should be allowed 
to stand at least 12 hours after filling before 
being ready for use. 

The Magneto—Advantages of. Without a 
proper supply of ignition current it is impos¬ 
sible for a motor, running with the best possible 
mixture of gasoline and air, to give its maxi¬ 
mum power. Both the dry battery and the 
storage batterv labor under the same disadvan- 
tage, viz.: that they are sources of current that 
are* entirely external to the motor, and must be 
periodically replenished, similar to gasoline and 
lubricating oil. Moreover, the changes which 
these batteries undergo are chemical and of 
course invisible, and if the batteries are not 
tested at stated periods, certain defects are not 
apparent until current is called for. A magneto 
on the other hand is a purely mechanical ap¬ 
paratus, operated by the engine, thus relieving 
the autoist of all anxieties resulting from de¬ 
pendence upon an outside source of current. 
An extended description of various types of 
magnetos, together with an explanation of the 
principles controlling their action, is given un¬ 
der the head of Magnetos. 

Igniters—Synchronizing of. The synchro¬ 
nizing of igniters is most easily and accurately 
done with the aid of one or two cells of battery 


The Automobile Handbook 


383 


and a volt-meter. If the battery is part of the 
standard reserve equipment it is not necessary 
to make any change in the connections, except 
to break the connection from the switch to the 
bus bar and insert the voltmeter. Then the 
spark lever is fully retarded, and the flywheel 
turned to one of the dead positions, which are 
usually marked on it. This position should be 
the breaking position for whichever igniter is in 
action at that instant. 

While contact is established the voltmeter 
will indicate the fact, and the instant contact is 
broken the needle will return to zero. Adjust 
the igniter rod up or down until on two or 
three successive trials the break occurs at ex¬ 
actly the right point, and see that tightening 
the locknut on the igniter rod does not change 
this adjustment. Turn the crank again and 
watch carefully the movement of the igniter 
rod after the contact is made. If it does not 
move up half its total travel after contact is 
made, take off the igniter plate, slacken the ta¬ 
per fit of the outer arm on the rocking stem, 
and turn the arm very slightly downward. Re¬ 
place the igniter plate and readjust the igniter 
rod. When the first cylinder has been satisfac¬ 
torily timed, take the second, and so on. It is 
best to cut out all the cylinders except the one 
under test. 

In a make-and-break igniter the grounded 
electrode is the rocking stem and finger. This 
stem is lubricated by what oil may chance to 


384 The Automobile Handbook 

pass it from the combustion chamber. Usually 
this oil is sufficient for lubrication, and it may 
be so abundant as to interfere with the flow of 
current. It is not uncommon to see sparks jump¬ 
ing' from this electrode to adjacent parts when 
the motor is running fast. In case misfiring is 
noted, and the insulation of the lava bushings 
is known to be good, a light coil spring may be 
connected between the rocking stem and any 



Fig. 164 

Hoyt Voltammeter Which Simplifies Ignition Testing 


adjacent grounded part, such as one of the studs 
holding the igniter plate. This spring should 
not be stiff enough to interfere with the make- 
and-break movement. Soft copper wire is the 
best material for it, and one end of the wire 
may be soldered to a copper “battery terminal” 
held by the stud nut, this making a permanent 
and reliable method of fastening electrical con¬ 
nections. 













The Automobile Handbook 


38 ? 


Ignition Testing. The life of an ignition bat¬ 
tery depends upon the current consumption of 
the spark coil, and if adjustments are made in 
conformity with the indications of current 
measuring instruments the battery will last 
much longer, and all parts of the ignition sys¬ 
tem will give better service. Too small a gap 



Fig. 165 

Wiring Diagram, Showing Coil Binding Posts 


at the vibrator increases current consumption, 
causing a rapid depletion of the battery, as well 
as pitting and sticking of the vibrator points. 
Too wide a gap lessens the current flow thus 
causing misfiring. 

The same proposition applies with equal force 
at the spark plug points. Figs. 164, 165 and 166 


















































386 


The Automobile Handbook 


illustrate a device known as a voltammeter 
which can be made a fixed part of the battery 
circuit, thus furnishing a continuous and visible 
record of battery performance under working 
conditions, and by means of which faults may be 
readily detected and remedied. The apparatus 
consists of two instruments, an ammeter and a 

i 

voltmeter, mounted on a common base that is 



Fig. 166 

Voltmeter Indicates Condition of Circuit 


attached by screws directly to the dash if of 
wood, or to an insulating block in case the dash 
is of metal. The voltage of the primary, or 
battery, circuit is measured by the instrument 
at the right, while the strength of the current 
in amperes is measured by the one at the left. 
Both instruments operate on what is commonly 
known as the D’Arsonval principle, a perma- 


































The Automobile Handbook 


387 


nent magnet being employed to create a strong 
magnetic field of practically unvarying inten¬ 
sity, within which a rectangular coil of fine 
wire, wound on a centrally pivoted aluminum 
open-frame bobbin, mounted between the pole 
pieces of the magnet, is made do rotate against 
the opposing influence of a spring, by the cur¬ 
rent that passes through it. Attached to the 
coil bobbin, or frame is a pointer that moves 
over a scale so graduated as to indicate the 
strength, (amperage) or the pressure, (voltage) 
of the current, causing a deflection of the swing¬ 
ing needle from its normal or zero position. Fig. 
165 shows the method of connecting the volt- 
ammeter, and it will be seen that the carbon, or 
positive ( + ) terminal of the dry cell battery A, 
and also positive ( + ) terminal of thp storage 
battery B are connected to the terminals of the 
coil C from which wires are led to the timer D 
by which the primary or dry cell circuit is 
closed. From the contact screw of either of 
the coil units a wire is led to the right hand 
binding post of the voltammeter, and the zinc 
or negative (—) terminals of both batteries are 
connected to the central (—) binding post of the 
instrument. The return circuit wire is con¬ 
nected to the left hand binding post of the 
voltammeter. The current loss due to the oper¬ 
ation of the instrument is reduced to a negligi¬ 
ble quantity, notwithstanding that the volt¬ 
meter is connected across the main leads as 
shown in Fig. 166. The ammeter is connected 


388 


The Automobile Handbook 


in series in tlie primary circuit, but the current 
is caused to pass through a shunt conductor S. 
H., Fig. 166, having somewhat higher resistance 
than the other parts of the circuit, but still of 
sufficiently low resistance to make the current 
loss due to its use a negligible factor also. 
The coil of the ammeter is connected in parallel 
with the shunt, forming a divided circuit, a very 
small portion of the current passing through 
the coil, while the rest passes through the shunt. 
Referring to Fig. 165, current from the primary 
battery A, or from the secondary battery B, 
whichever happens to be in use, passes through 
the primary winding of the coil C when the 
circuit is closed by the timer D. 

From coil C current flows into the voltmeter 
through the wire attached to the right hand 
binding post, and thence back to the battery. 
When the timer closes the circuit through the 
coil, a portion of the current that flows through 
the timer ground circuit passes into the amme¬ 
ter and out to the center binding post, thence 
back to the battery. The largest portion of the 
current passes directly from the left hand 
binding post to the center binding post through 
shunt S, H, Fig. 166. The return circuit be¬ 
tween tinier D and engine F, Fig. 165, is indi¬ 
cated by the dotted line, the direction of flow 
being shown by the arrows. In Fig. 166 the 
voltmeter circuit when switch S is closed is in¬ 
dicated by the dot and dash line. Current 
from dry battery D, B, flows through primary 


The Automobile Handbook 


389 


P 1 , timer T, ground and left binding post of 
volt a mme ter, passes through shunt S, H, and 
ammeter coil A. 

To make a test with the device, first make the 
distance between spark plug points as nearly 
uniform as possible, the gap not to exceed .03 
in., and then file the platinum points of the vi¬ 
brators and contact screws so that they are flat 
and true as well as smooth. After filing the 
points, the contact screws of each unit should 
be adjusted so as to give the vibrator 1-16 in. 
play between screw and iron core. Then with 
the gasoline supply to the carbureter shut off, 
and compression relief cocks open, turn the en¬ 
gine over until the timer makes contact and 
sparking occurs in one of the cylinders. Note 
the reading of the ammeter when the timer 
closes the primary circuit, and if the current 
consumption of the coil exceeds .8 ampere, in¬ 
crease the vibrator gap by unscrewing the con¬ 
tact screw, thus decreasing the flow of current. 
Should the vibrator fail to act, however, screw 
down the contact screw thus decreasing the gap 
until the vibrator acts. Proceed in this manner 
to adjust each of the vibrators until the cur¬ 
rent consumption is the same on all. 

In making adjustments while the engine is at 
rest it is necessary to adjust for a current con¬ 
sumption about twice as great as is desired in 
actual operation owing to the fact that when 
the engine is at rest the circuit is closed for a 


390 


The Automobile Handbook 


considerably longer time than when running 
and the How of current is intermittent. 

Thus if a two unit coil be adjusted to take 
$4 ampere while at rest, it would consume only 
% to % ampere while engine is in operation. 
With the car in operation, a glance at the am¬ 
meter will show whether there is a normal flow 
of current through the coil. The instrument 
will also serve as a reliable guide in the location 
of ignition troubles and their remedies as may 
be seen by the following table: 


The Automobile Handbook 


391 


TABLE OF COMMON IGNITION TROUBLES AND 

REMEDIES. 


Reading 

of 

Voltmeter 

Corresponding 

Ammeter 

Reading 

Cause 

Remedy 

Steady. .. . 

Regular. 

Normal condi¬ 
tions. 

None necessary. 

Oscillating 

needle. 

Irregular. ... 

Loose contact in 
battery circuit— 
Leakage of sec¬ 
ondary current 
—Short circuit 
or exhausted 
cells 

Tighten connec¬ 
tions—See that 
timer contact is 
made evenly— 
Eliminate leak¬ 
age. 

Uniform or 
gradual 
drop. 

Regular. 

Normal deterior¬ 
ation of battery. 

None required. 

Abnormal 

drop. 

High. 

Rapid deteriora¬ 
tion of battery 
because of short 
circuit at plug or 
in battery box— 
Improper adjust¬ 
ment of coil-vi¬ 
brator or spark, 
plug gaps, latter 
being too narrow 
—One or two 
exhausted cells. 

Eliminate short 
circuit — Read¬ 
just vibrator and 
spark gaps—Re¬ 
move exhausted 
cells. 

Normal. . . 

Low. 

I‘oor contact in 
timer, vibrator, 
or connections— 
Short circuiting 
of cells. 

Clean contacts, 
eliminating ef¬ 
fects of corrosion 
or wear. 

Normal. . . 

High. 

Sooted spark plug 
—Gaps at vibra¬ 
tor or spark plug 
too small — De¬ 
creased coil effi¬ 
ciency. 

Clean spark plugs 
—Increase width 
of gaps — Read¬ 
just tension of 
vibrator spring. 

Normal. . . 

Irregular.... 

Poor timer con¬ 
tact. 

Fix timer. 

Normal. . . 

Zero. 

Broken ground 
wire. 

Put in new wire. 

Zero. 

Zero. 

Broken wire be¬ 
tween coil and 
battery or brok¬ 
en battery con¬ 
nections. 

Put in new wire. 

























































392 


The Automobile Handbook 


Ignition—Timing. In timing the ignition of 
a motor one should base his operations on one 
particular cylinder, and this should be the most 
accessible one. Let it be assumed that a me¬ 
chanic is required to test or correct the timing 
of a four-cylinder, four-cycle vertical engine. 
He would have to know the order in which the 
cylinders fired, and how to find the firing center 
of No. 1 cylinder. As the operation of the 
valves on most motors may be readily seen, the 
firing center and the order in which the cylin¬ 
ders fire can be easily learned from the action 
of either set. For instance, if on turning the 
motor over slowly the intake valve of No. 1 
cylinder opens and closes, then that of No. 3 
cylinder, and following No. 3 that of No. 4 op¬ 
erates, the mechanic need go no further, for he 
knows that the engine fires 1-3-4-2. The ex¬ 
haust valves, of course, may be used in the same 
way. IIoAvever, if the valves are entirely en¬ 
closed, as on the Winton cars, open the priming 
or relief cocks, and beginning with cylinder No. 
1 note the order in which the air is forced out 
through the cocks. There are two rules for 
finding which cylinder is on its firing center, 
that are based on the action of the valves; these 
are as follows: When an exhaust valve is open 
the following cylinder is about to fire. When 
an intake valve is open the previous cylinder is 
about to fire. One very simple method of find¬ 
ing the firing center of a cylinder is to open 
the priming cocks of all the cylinders but one, 


The Automobile Handbook 


393 



Fig. 

1 —Ba tter y. 

2 and 3—Primary wires. 

4— Vibrator. 

5— Contact screw. 

6— Crank case. 

7— Cylinder. 

8— Induction coil. 


167 

0—Condenser. 

10— Commutator. 

11— Contact maker. 

12— Commutator case. 

13— Switch. 

14 and 15—Secondary wires. 
16—Spark plug. 


turn the motor over slowly till compression is 
encountered, open the cock, insert a stiff wire* 
till it rests on the piston head, then carefully 
bring the piston to the top of its stroke. The 
























































394 


The Automobile Handbook 


cylinder will then be on its firing center. When 
the firing center, and the order in which the cyl¬ 
inders fire are known, all that remains to be 
done in timing an engine is to set the revolving 
segment of the commutator or distributor so 
that a spark will occur in the proper cylinder 
when the spark control lever is advanced about 
one-third or, with the spark control lever fully 
retarded, and the piston about % to 1 inch 
down on the explosion stroke, set the segment 
so that it just begins to make contact. 

Ignition—Wiring Diagrams. Fig. 167 illus¬ 
trates the ignition circuit of a single cylinder 
motor, showing plainly the battery, coil and 
commutator connections. A reference table 
accompanies Fig. 167, giving the names of the 
various parts shown in the drawing of the igni¬ 
tion circuit. 

Fig. 168 shows connections for four cylinder 
ignition in which the timing of the spark is 
controlled by the rotation of a single timer V 
around shaft E. 

This varies the point in the engine cycle at 
which the cam E acts on each spring. Wear in 
the timer is taken up by adjusting the platinum 
points. Either storage batteries or dry cells 
may be used in this system as desired. 

The objections to this system have been that 
the arrangement of contact points often gets out 
of order, owing to their delicacy of adjustment, 
the inaccessibility of the timer, the tendency 
of the springs to break, and the ease with which 


The Automobile Handbook 395 

the contact may become broken by means of oil 
or dirt, this system is classed as a mechanical 
make and break system, owing to the fact that 
the spark is caused by the abrupt mechanical 
action of the contact spring. Another system 
known as the multiple vibrator coil ignition sys¬ 
tem is illustrated in Figs. 169, 170, 171, 172 and 
173. 



Fig. 168 

Diagram of Connections for Four-Cylinder Ignition With 
Four Coils and One Timer 


In this system each coil has its own vibrator, 
which depends for its action upon the electrical 
make-and-break instead of the mechanical timer 
as shown in Fig. 168. Referring to Fig. 169, 
the timer consists of an insulated cylinder I, 
loosely carried by a sleeve on the two to one 
shaft. On the inside of this cylinder are dis¬ 
posed at regular intervals the contact segments 
1\, K, K, K, and fixed to the shaft is the moving 


















































396 


The Automobile Handbook 


brush E, which makes a wiping contact success¬ 
ively with each of the fixed segments. 

The electrical connections in this system are 
as follows: When the brush is rotated into con¬ 
tact with segment K, the circuit is through wire 



W to contact screw of the vibrator of coil 
thence into the vibrator spring and into one 
end of the primary winding of the coil, out at 
the other end thereof to the common wire M, 
through the switch S, and through one or other 


























































The Automobile Handbook 


397 


of the two battery sets to the engine frame, 
thence through the two to one shaft, and through 
the timer brush to the starting point, the in¬ 
duced secondary discharge giving rise to a 
spark at plug P. When the contact is made be¬ 
tween the brush E, and the segments K, K and K 
respectively, coils C, C and C respectively act, 
producing successions of sparks in plugs P, P 
and P. The rapidity and power of the sparks 



produced by the several coils largely depend 
upon the adjustment of their respective vibra¬ 
tors. If a vibrator is adjusted too lightly, it 
may break the circuit before the coil is charged 
adequately to produce a spark of full power, 
and if too stiffly adjusted it may hold contact 
until the coil has been charged for too long a 
period, thus causing a waste of current, al¬ 
though producing a good spark. Incorrect ad- 



























398 


The Automobile Handbook 


justments may also cause differences in the 
amount of power developed in the several cylin¬ 
ders, causing a generally unsatisfactory action 
of the motor. The advantages of this system 
over the mechanical make-and-break vibrator 
are: The absence of delicate platinum or steel 
springs; and that the coils may be mounted on 
the dash, where they are easy of access. 


Plug 



In order to obviate lack of uniformity be¬ 
tween the sparks in the different cylinders, and 
at the same time to save some outlay in coils 
and reduce the necessary wiring, the single coil 
distributor system, diagrammatically illustrated 
in Fig. 173, is employed, the distributer being 
merely a device designed to direct the discharge 
of the single coil to the spark plug of each cyl- 


































































































The Automobile Handbook 399 

inder in rotation. The timer T is of the brush 
and segment type, driven by or from the two to 
one shaft. It is provided with four equally 
spaced contact segments K, K,, K, K, which in¬ 
stead of being wired to separate coils, are all 
electrically connected by a metal ring, which 
is connected to one primary terminal of the 
single vibrator coil. Distributer D is also 
mounted and driven by the two to one shaft. 


Tremblers 



K A 


Fisr. 172 


Diagram of Wiring of a Four-Unit Vibrator Coil 


For clearness this distributer is shown sepa¬ 
rately, although it is generally made integral 
with the timer. It consists of an insulated shell 
carrying four metallic segments L, L, L, L. 
Within is a continuous metallic ring R. The ro¬ 
tating arm M is insulated from the two to one 
shaft, and carries at its outer end a brush, ar¬ 
ranged to bear upon the segments and ring R, 
or to pass in very close proximity thereto. Seg¬ 
ments L connected by wires W to plugs P. One 
of the secondary terminals of coil C is connected 





















400 


The Automobile Handbook 


to ring R, and the other to the engine frame or 
ground. 

The action is as follows : 


Suppose that the brushes of the timer and 
distributer are in the position shown, the path 



of the primary current will then be as follows: 
From segment Iv the current will flow through 
tin* common ring along wire F to one primary 
teiminal to the coil box (J, through the vibrator 
contact screw and vibrator spring V, through 














































The Automobile Handbook 


401 


the primary winding, out at the other primary 
terminal of the coil, through the switch S, 
through one or the other of the batteries B into 
the engine frame, through the secondary shaft 
and timer brush to the starting point. The 
course of the secondary discharge will be as 
follows: From secondary coil terminal E, 
through wire II to the common ring R, of the 
distributer, through the brush carried by the 
revolving insulated arm to segment L, out 
through wire W to the insulated terminal of 
plug P, through the air gap of the plug to the. 
engine frame, up through wire X, from the en¬ 
gine to the other secondary coil terminal, and 
thence through the secondary winding to the 
starting point. All four cylinders are thus 
sparked in rotation from a single coil, and as 
the vibrator of this coil determines the dis¬ 
charge in each one of the four cylinders, igni¬ 
tion is uniform in point of time. This is termed 
synchronous ignition. The timing of the spark 
is changed by rotating the timer and distributer 
around the shaft, the length of the segments 
being sufficient to allow of this, and still main¬ 
tain contact with the brush, even at the ex¬ 
tremes of spark advance and retardation. The 
main disadvantage connected with the single 
vibrator high tension system is that the high 
tension current is brought into close proximity 
to “ground” in the distributer, and if the in¬ 
sulation becomes impaired it may escape there, 
or at times jump to the wrong segment and 


402 


The Automobile Handbook 


spark the wrong cylinder. In any single vi¬ 
brator system there is almost constant work de¬ 
manded of this vibrator, and other things being 
equal' it naturally wears several times as fast 
as a vibrator sparking but one cylinder. 

In all jump-spark systems of ignition.in which 
the circuit is interrupted between platinum con¬ 
tacts, the condenser plays a very essential role 
in reducing the burning of these contacts, al¬ 
though its chief office is in increasing the ab¬ 
ruptness with which the current is interrupted, 
and hence augmenting the discharge pressure. 

When to Retard the Ignition. Always re¬ 
retard the ignition before starting the motor, 
and take great care that the ignition is retarded 
and not by mistake advanced. Some cars arc* 
fitted with a de\ ice which prevents the starting 
crank being turned unless the spark is retarded. 
If it is not clear as to which way to move the 
ignition lever to retard the ignition, move the 
commutator in the same direction as the cam¬ 
shaft rotates. 

As soon as the motor slows a little when go¬ 
ing uphill, retarding the spark enables more 
power to be obtained from the motor at the 
slow speed, that is to say, if the spark is not 
retarded the motor Avill go slower than if it is 
retarded. Do not retard the lever to the utmost 
under these conditions; on the contrary, retard 
the lever to such a point that the knocking (due 
to the wrong position) ceases. 

Retarding the spark causes the maximum 


s he following description and wiring diagram of Jump Spark Ignition Systems were copied from the Nov. 3, 
1910, issue ot ‘Motor Age,’ and show in a graphic manner the connections and relative arrangement of the 
leading features: 

8—Spark plugs sooted 


“In Fig. 173a a wiring diagram is given, repre¬ 
senting the relative arrangement of the features 
of four popular types of jump spark ignition 
systems, including a single battery system, a 
single high-tension magneto system, a dual low- 
tension magneto system, and a double ignition 
system with a high-tension magneto, and a bat¬ 
tery, coil and timer. In the single battery sys¬ 
tem, when the switch S is closed, current flows 
from the battery to the four-unit vibrating coils, 
on through one of the coils, and oue of the pri¬ 
mary wires LI, L2, L3, or L4, according to the 
position of the revolving segment of the timer, 
and then returns to the battery through the 
ground wire G. The secondary current generated 
in the coils every time a primary circuit is 
broken passes through one of the respective wires 
HI, H2, H3, or H4, to the spark plug in the 
cylinder. In the single high-tension magneto 
system, both the primary and secondary currents 
are generated in the high-tension magneto and 
pass through the cables Ml, M2, M3 or M4 to 
the spark plugs. 

The features of the dual system include a low- 
tension magneto and battery as sources of cur¬ 
rent, a non-vibrating induction coil and one set 
of plugs. In this system, when the switch on the 
coil is on the battery side B, the current flows 
from the positive pole of the battery through 
the wire C to the coil, and then to the circuit 
breaker-box B1 on the magneto through wire 
PI, where, when connection is made, the current 
flows back to the coil-box through P2 and re¬ 
turns to the battery through Cl. The primary 
current is broken in the circuit-breaking box Bl, 
generating the induced currents in the non-vi¬ 
brating coil and these high-tension currents flow 


to the distributor D of the magneto through the 
heavily-insulated wire P, and then pass on to the 
spark plugs through one of the wires Wl, W2, 
W3, and W4. When the battery switch is turned 
to the magneto side M the primary current flows 
from the magneto to the coil through the wire 
PI, and when the connection is made in the cir¬ 
cuit-breaker box Bl it returns through wire P3. 
And when the circuit is broken in the breaker- 
box the high-tension currents induced in the coil 
go to the distributor and on to the spark plugs 
just as when the battery was employed. 

In a double ignition system there are two 
independent ignition systems. In this diagram 
the battery system above described would com¬ 
prise one of the systems, and the high-tension 
magneto system the other. The switch SI on the 
coil box of the battery system and the wires MG 
and GG leading to the magneto are merely em¬ 
ployed to short circuit the primary current of 
the magneto and prevent the induction of the 
high-tension currents required at the spark plugs 
when it is desired to cut this system out of ac¬ 
tion. The double system requires two sets of 
plugs, one for each system as indicated.” 

CAUSES OF TROUBLE 
No explosions— 

1— Switch off 

2— Batteries exhausted 

3— Battery to switch wires short-circuited 

4— Switch out of order 

5— Magneto short-circuited 

6— Broken battery connection 

7— Batteries nearly exhausted 

Regular miss-firing, one or more cylin¬ 
ders— 


9—Insulation cracked 

10— High-tension cables short-circuited 

11— Timer to coil wires short-circuited 

12— Vibrators out of adjustment 

13— —Magneto distributor contacts worn 

14— Spark plug points out of adjustment 

Irregular miss-firing, one or more cylin¬ 
ders— 

15— Batteries weak 

16— Defective wiring 

17— Dirt or loose metal in timer 

18— Loose connections 

REMEDIES 
No explosions— 

1— Turn on switch 

2— Recharge or replace batteries 

3— Test with fresh wire 

4— Attach or shunt wires around switch 

5— Remove wire to switch, crank motor 

6— Tighten all connections 

7— Readjust vibrators on coils 

Regular miss-firing, one or more cylin¬ 
ders— 

8— Remove and clean 

9— Replace with good plug 

10— Separate from metal of engine 

11— Rewire 

12— Readjust aid clean points 

13— Renew brushes or stretch springs 

14— Space fa ineh 

Irregular miss-firing, one or more cylin¬ 
ders— 

15 — Recharge or renew battery 

16— Insulate or renew wiring 

17— Clean timer 

18— Find and tighten 



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The Automobile Handbook 


403 


pressure of the explosion to occur at the best 
part of the stroke, or, rather, the mean pressure 
of the explosion stroke will be lower if the best 
point of ignition by retarding is not found. This 
is a matter of some skill and practice. 

To slow the motor, cut off as much mixture 
as the throttle allows, then slow the motor still 
further by retarding the spark, but on no ac¬ 
count retard the spark when the throttle is full 
open (for the purpose of slowing the motor), 
as the motor will merely discharge a quantity 
of flame at a white heat over the stem of the 
exhaust valve, burning it, softening it, and 
making it scale. 

When to Advance the Ignition. With too 
early ignition the pressure upon the piston be¬ 
comes excessive and without any adequate re¬ 
turn of useful work or energy. If the ignition 
he retarded too much, the maximum explosive 
pressure occurs too late during the working 
or power stroke of the piston, and the combus¬ 
tion of the gases is not complete when the ex¬ 
haust-valve opens. Greater motor speed re¬ 
quires an early ignition of the charge, but 
greater power calls for late or retarded igni¬ 
tion. 

The reason for advancing the spark when 
fast running is required, is that the explosion 
or ignition of the charge is not instantaneous 
as may be supposed, but requires a brief -inter¬ 
val of time for its completion. 

It may be well to explain without entering 


404 


The Automobile Handbook 


into theoretical details, that when a motor is 
running at normal speed, the ignition-device is 
so set that ignition takes place before the pis¬ 
ton reaches the end of its stroke. The later 
the ignition takes place the slower the speed 
of the motor and consequently the less power it 
Avill develop. If, however, in starting the mo¬ 
tor the ignition-device were set to operate be¬ 
fore the piston reached the end of its stroke, 
backfiring would occur, resulting in a reversal 
of the operation of the motor and possibly in 
injury to the operator. 

Ignition Troubles—Remedies For. Trouble 
may occur from the cam or commutator not be¬ 
ing properly adjusted. The contact-screw of 
the induction coil vibrator may be loose. 

The vibrator or trembler of the coil may not 
be properly adjusted. 

To adjust the vibrator, turn the motor crank 
until the contact is closed, throw in the switch 
and listen for a good clear buzz from the vi¬ 
brator. Do not allow it to buzz slowly but fast, 
until it makes a singing sound like a bumble 
bee, then turn the crank several times and 
again listen for the buzz. Sometimes the vi¬ 
brator will buzz, but it will not buzz when the 
motor is running fast and the motor misfires; 
this is probably due to the fact that the adjust¬ 
ing screw has made the tension of the spring 
too strong, and when a quick contact is made it 
does not have time to vibrate properly. Expe- 


The Automobile Handbook 


405 


rience is the only teacher for properly adjust¬ 
ing the vibrator of an induction coil. 

Many troubles arise from faulty or defective 
insulation. 

A wire placed too close to an exhaust-pipe 
invariably fails after a time, owing to the insu¬ 
lation becoming burnt by the heat of the pipe. 

A loose wire hanging against a sharp edge 
will invariably chafe through in course of time. 

If the insulation of the coil breaks down it 
cannot be repaired on the road, it should be re¬ 
turned to the makers. A slight ticking is 
usually audible inside the coil when this occurs. 

All wires where joined together should be 
carefully soldered, the joints being afterwards 
insulated with rubber or prepared tape. Never 
make a joint in the secondary wires. See that 
all terminals are tightly screwed up. When 
connecting insulated wire, the insulation must 
be removed, so that only the bare wire is at¬ 
tached. Wires sometimes become broken, and 
being loose make only a partial contact. 

Battery ‘terminals frequently become cor¬ 
roded ; they should be covered with vaseline, 
and require periodical cleaning. See that all 
connections at the battery are clean and bright. 

The porcelain of the spark plug may be 
cracked and the current jumping across the 
fracture. The points may be sooty and require 
cleaning. They may be touching and require 
separating, or they may be too far apart. The 
usual distance between the points is about one 


406 


The Automobile Handbook 


thirty-second of an inch, which is approxi¬ 
mately the thickness of a heavy business card. 

Clean all oil and dirt from the commutator. 
Most commutators are so placed as to give the 
maximum possible opportunity to collect oil 
and dirt. They should always be provided with 
a cover. 

In course of time dry or storage batteries 
will become weak or discharged. Always carry 
an extra 'set. 

Spanners, oil-cans, tire-pumps, etc., have been 
known to get on the top of the batteries, 
thereby connecting the terminals together and 
causing a short-circuit. 

The platinum contacts of the coil may be¬ 
come corroded. They should be cleaned with a 
small piece of emery cloth or sandpaper. 

The platinum points on the trembler may 

i 

become loose. They should be riveted up with 
a small hammer. 

It frequently happens that oil and dirt accu¬ 
mulate on the platinum contacts, which inter¬ 
rupt the free flow of the current. Care should 
be taken, therefore, that they are always per¬ 
fectly clean. 

Indicator. An indicator consists of a small 
cylinder within which works a piston under the 
tension of a helical spring of predetermined 
strength. The rod attached to the piston car¬ 
ries a pivoted arm which works on a horizontal 
lever. This lever carries a pencil bearing 
against a drum. This drum is so arranged 


The Automobile Handbook 


407 


with a spring that it may be partially rotated 
by the pull on an attached string. A sheet of 
paper is wound on the drum and held in place 
by spring clips. The pressure in the cylinder 
acting on the spring causes the pencil to mark 
the paper, the indicator card or diagram being 
traced by the forward and backward movement 



of the drum. Fig. 174 is a semi-sectional view 
of a Crosby indicator with small piston in place 
for explosive motor work. The pencil arm is 
of extra strength to withstand the shock due to 
the explosive pressure exerted upon the piston. 
Fig. 175 shows the new Crosby indicator de¬ 
signed for taking continuous diagrams. The 

















408 


The Automobile Handbook 


drum is designed to use a roll of paper 2 inches 
wide and 12 feet long, upon which is made in 
the operation of the indicator a series of dia- 



Fig. 175 


grams. In the center of, and concentric with 
the drum is a cylinder upon which the paper 
is wound as it is used. When the roll is ex¬ 
hausted, the cylinder can be withdrawn 

























































































The Automobile Handbook 


409 


through an opening in the top of the drum, and 
the paper easily detached. Above the cylinder 
is a knurled head loosely attached to the drum 
spindle which may be adjusted to take contin¬ 
uous diagrams, varying in number from 6 to 
100 per foot of paper. Fig. 176 shows the Ta¬ 
bor indicator. The view of the cylinder being 
transparent, the small piston may be seen in¬ 
side. The spring is placed outside of the cylin¬ 
der in order that the hot gases from the engine 
will not affect its temper, and thereby change 
its tension. 

All indicators of this type, employing a pres¬ 
sure piston and spring, require careful calibra¬ 
tion where extreme accuracy is essential. On 
account of the inertia of the piston and pencil 
mechanism, and that of the oscillating drum, en¬ 
gines of very high speed cannot be indicated 
by the forms of indicator just described. They 
have been found to be reasonably accurate at 
speeds as high as 500 revolutions per minute, 
although at this speed they can be used success- 
• fully only by experienced hands. 

Indicators for High Speed. To overcome 
this objection and to be able to indicate engines 
of speeds as high as 2,000 revolutions per min¬ 
ute or more, indicators employing a beam of 
light thrown upon a sensitive photographic 
plate are now used. In this case a small mirror 
is caused to move in two planes at right angles 
to each other, one movement being produced 
by the motion of the piston, the other by the 


410 


The Automobile Handbook 



Fig. 176 

Tabor Indicator With Outside Spring 









The Automobile Handbook 


411 


pressure, which is transmitted through a thin 
steel diaphragm. The angular motion of the 
mirror is so small, and the parts so light that 
the effect of inertia becomes practically negli¬ 
gible. 

Fig. 177 shows the general appearance, and 
Fig. 178 two sections of one type of the indica¬ 
tor referred to. This instrument is called the 
Hospitalier-Carpenter Manograph and is manu¬ 
factured in Paris. 

Some makers manufacture special heavy in- 

ACETYLENE 
B UR ME A 



dicators with ^4-inch pistons to suit the pres¬ 
sures involved in gas engine indication. Springs 
from 80 pounds to 200 pounds scale are very 
efficient in recording expansion, combustion 
and compression lines, as these effects are all 
high pressure. If the low pressure lines, such 
as the suction and exhaust, do not show up to 
advantage when taken with high scale springs, 
low scale springs of from 10 lbs. to 30 lbs. may 
be used for obtaining these lines. 

Indicator Diagrams. Fig. 179 shows a char- 












412 


The Automobile Handbook 


acteristic diagram from a four cycle engine. On 
the forward stroke of the engine the piston 
draws into the cylinder a charge of explosive 
mixture, the pencil of the indicator tracing the 
line A-B. It will be seen that this line drops 
slightly below the atmospheric line A-F. This 
slight drop is due to the partial vacuum pro¬ 
duced within the cylinder during the “suction 



GROUND 
CLASS - 

SCRCCN 


TOP VIEW SECTION 

F ig. 17S 

High Speed Engine Indicator 


stroke” of the engine. From point B, the pis¬ 
ton returns to its original position compressing 
the mixture in the clearance space, the indica¬ 
tor tracing the line B-C, which is known as the 
compression curve. At this point ignition takes 
place with a sudden increase in pressure, the 
indicator tracing the line C-D, which is nearly 
vertical. On the next or third stroke, the gases 
are expanded to point E. at which time the ex¬ 
haust valve opens, the indicator having traced 







































The Automobile Handbook 


413 


the line D-E which is known as the expansion 
curve. At E there is a drop in pressure as the 
gases issue from the exhaust port and from F 
to A the gases are swept from the cylinder 
which causes a line to be drawn by the indica¬ 
tor slightly above the atmospheric line A-F, as 
shown. This completes the cycle. The vertical 
distance from the atmospheric line to point C 
is proportioned to the compression pressure 
above atmosphere; the distance to point D is 


o 



proportional to the explosion or maximum pres¬ 
sure, and the distance to point E is proportional 
to the release pressure. 

Figure 180 shows a card from a two-port two- 
cycle gas engine. It will be noticed that the 
suction and exhaust lines are absent, the suc¬ 
tion stroke being completed in an enclosed 
crank case, or a separate cylinder or pump. The 
exhaust takes place at A and requires about 
one-tenth of the stroke. The exhaust and inlet 







414 


The Automobile Handbook 


ports are covered and uncovered by the piston 
and are definitely fixed points. 

Figure 181 shows a very good diagram, where 
combustion is very nearly complete, the mix¬ 
ture of air and gas being practically correct. 



The ignition line points slightly to the right at 
the top, and is nearly perpendicular. The ex¬ 
haust is shown to open at the right time about 
ninety degrees of the stroke. The suction and 
exhaust lines run very near the atmosnheric 



line, thereby denoting correctly proportioned 
inlet, and exhaust valves, and passages for 
same. 

Indicated Horse Power. The thermal or heat 
efficiency of an explosive motor may be deter- 










The Automobile Handbook 


415 


mined from an indicator diagram, which gives 
a representation of the internal conditions 
throughout the entire cycle of operations. The 
diagram tells many things essential to be 
known. 

It gives the initial explosive pressure, or 
the pressure a moment after ignition has taken 
place. It shows whether the volume of the 
charge is diminished during the period of ad¬ 
mission. It gives the point of ignition, when 
the ignition is complete, and when expansion 
begins. It indicates the pressure of expansion 
during the working stroke. It gives the termi¬ 
nal pressure when the exhaust is opened. It 
shows the rapidity of the exhaust. It indicates 
the back-pressure on the piston, due to the ex¬ 
haust. It shows the point of opening of the 
exhaust. It gives the mean power used in driv¬ 
ing the motor. It also indicates any leakage 
of valves or piston. 

The usual method of ascertaining the area of 
an indicator diagram is by means of an instru¬ 
ment known as a planimeter, which is used to 
calculate the area of any irregular surface, by 
moving a tracing point attached to the instru¬ 
ment over the entire irregular boundary line of 
the figure. 

But for the purpose of ascertaining the horse¬ 
power of a motor it will be sufficiently accurate 
to illustrate the principles involved, to calculate 
the area of the diagram by means of ordinates 
or vertical measurements. 


416 


The Automobile Handbook 


The upper drawing in Fig. 182 represents a 
card taken from a motor of 4 inches bore and 
6 inches stroke, with a speed of 900 revolutions 
per minute, and under a full load. The dia¬ 
gram is divided into 12 parts as shown by ver¬ 
tical lines, the lengths of which are in terms of 

r — 

( 


150 - 

l\ 1,00 





200— 

V1.39 





160 - 

1 





100— 

1 • 

• 










JO - 


•st 


•to 




J-L | 1 

i i 

i 


0 — 

—i—|—i—i— 

1 1 1 1 

■ i 

1 



I 2 

1 4 

s 


6 



Fig. 182 

the spring, which is 100. Then 1.90 -f- 1.36 -f- 
1.00, etc*, divided by 12, equals 0.665 as the av¬ 
erage height of the diagram. Its length is as¬ 
sumed to be 6 inches, therefore the area of the 
card is approximately 3.99 square inches. As 
the initial explosive force from the diagram is 
250 pounds per square inch, and a 100 indicator 













The Automobile Handbook 


417 


spring used, the height of the card is 250 
divided by 100, which equals 2 1 /> inches. 
The mean effective pressure on the piston in 
pounds per square inch will therefore be equal 
to the area of the diagram 3.99, divided by the 
area of the whole card, which is 2% X 6, equals 
15, and multiplied by 250, the initial explosive 
force, or 3.99 X 250, and divided by 15, equals 
66.5 pounds per square inch as the mean effect¬ 
ive pressure required. 

From this the indicated horsepower of the 
motor can readily be found as follows: 

Let M.P be the mean effective pressure in 
pounds per square inch, A the area of the cyl¬ 
inder in square inches, S the stroke of the pis¬ 
ton in inches, N the number of explosions per 
minute, and II.P the indicated horsepower, then 

M.P X A X S X N 

H.P =- 

396,000 

66.5 X 12.56 X 6 X 450 

=--= 5.69 

396,000 

as the required indicated horsepower of the 
motor. The indicated horsepower of any motor 
will always be greater than that obtained from 
a brake test, as it simply represents the actual 
thermo-dvnamic (heat-pressure) conditions 
within the cylinder, and takes no account of 
friction and other external losses. 




418 


The Automobile Handbook 


The lower drawing in Fig. 182 is a card 
taken from the same motor running under half 
load. 

Induction Coil. The form of coil generally 
used on gasoline cars is known as the jump- 
spark coil. It is of two types, one known as a 
plain or single jump-spark, the other as a vi¬ 
brator or trembler coil. 

A jump-spark coil consists essentially of a 
bundle of soft iron wire, known as the core, 
over which are wound several layers of coarse 
or large size insulated copper wire, called the 
primary winding. Over this are again wound 
a great many thousand turns of very fine or 
small wire, known as the secondary winding. 

Inertia. Inertia is that property of a body 
by which it tends to continue in the state of 
rest or motion in which it may be placed, until 
acted upon by some force. As used by the non¬ 
technical, it is almost universally employed in 
the former sense, i. e., that of the resistance 
which a body offers against a change in its po¬ 
sition, an inert body usually being intended, so 
that the definition is perfectly correct so far 
as it goes. The popular impression is that only 
inert bodies have inertia, it being likewise gen¬ 
erally thought that a moving body is possessed 
of momentum alone, whereas an object at rest 
is possessed of inertia, and the same object in 
movement has both momentum and inertia. 

Insulating Material. Asbestos, lava, and mica. 


The Automobile Handbook 


419 


are severally used for the insulation of spark 
plugs and sparking devices. 

Vulcanized fiber or hard rubber or even hard 
wood are used for the bases of switches, con¬ 
nection boards, etc. 

India rubber, or gutta-percha form the basis 
of the insulated covering of wires used for elec¬ 
trical purposes. The coils of small magnets and 
the cores of induction coils are usually wound 
with cotton covered wire, or in some instances 
the fine wire is silk covered, as in the case of 
secondary or jump-spark coils. 

Instructions for Starting and Stopping. The 
regular order for starting an automobile engine 
is given in the following paragraphs. This or¬ 
der should be followed every time the engine is 
started, for this is the best way to avoid forget¬ 
ting things; in fact, the beginner will do w^ell 
to memorize these instructions. 

1. Open the main gasoline valve at the tank. 
If the tank is hung low-, and the gasoline is 
lifted to the carbureter by air pressure, ascer¬ 
tain—by priming the carbureter if necessary— 
that the tank has the required pressure, and 
pump air into it by hand, if necessary. A hand 
pump for this purpose is mounted on the dash, 
usually at the left end. Sometimes the gasoline 
passes through a small auxiliary tank on the 
dash, and this tank holds gasoline enough to 
supply the carbureter by gravity until pressure 
from the exhaust gases can be raised in the 
main tank. 


420 


The Automibile Handbook 


2. Retard the spark as far as possible. This 
is of the first importance, as the attempt to start 
with the spark advanced may result in a bro¬ 
ken arm. It is an excellent rule never to turn 
the starting crank, even when it is thought that 
no explosion can occur, without first seeing to 
it that the spark lever is retarded. 

3. Set the throttle about one-quarter open. 

4. Close the switch and insert the safety 
plug, if one is used. 

5. Turn on the oil feed. It is assumed that 
any oiling and filling of oil cups done by hand 
has already been attended to. 

6. Open the compression relief cocks, if 
there are any. 

7. Prime the carbureter, by depressing the 
float or otherwise, according to its construction. 
If the motor has been stopped for not more 
than an hour or two, or sometimes longer, this 
is- not necessary. If the tank has pressure feed, 
and the carbureter has been primed to test the 
pressure (see 1), it does not need to be primed 
again. 

8. Engage the starting crank, and turn it 
over until the resistance due to the compression 
stroke is felt. If the starting crank is not now 
on its up stroke, move it backwards a quarter 
or half turn until it is, and reengage the 
ratchet at this new point. Never push the crank 
over the compression stroke. Even if the switch 
is open, a hot motor may start from pre-ignition, 
and a “back kick” may result in a broken arm. 


The Automobile Handbook 


421 


9. Pall the starting crank upwards smartly 
against the compression. The motor may start. 
If it does not, turn the starting crank until the 
next compression stroke comes, and pull it up¬ 
wards smartly as before. 

If the carbureter has not been primed too 
much or too little, the motor should start unless 
the gasoline is too cold to vaporize. If it does 
not start with the second or third trial, prime 
the carbureter again and repeat the operation. 
If the motor still refuses to start, something 
may have been negleced or forgotten. It may 
be that the gasoline is not turned on, that there 
is no gasoline in the tank, or that it is stale or 
heavy, that the switch plug is not in place, that 
the battery is not strong enough, or that the 
method of priming the carbureter has given too 
light or too weak a mixture. The method of 
priming is something that will depend on the 
individual carbureter, and can only be learned 
by experience. 

The procedure for stopping an automobile en¬ 
gine is to partly close the throttle so that the 
motor will run slowly and then open the switch; 
if the stop is permanent, take out the safety 
plug, shut off the oil feed, and shut off the gas¬ 
oline at the tank. If the car has been run some 
distance it is well to squirt a small amount of 
kerosene through the compression relief cocks 
to loosen any carbon deposit that may have 
gathered around the piston rings. 

Jacket—Water. Water-jackets that are cast 


422 


The Automobile Handbook 


with the cylinder have the disadvantage that 
they cannot readily be cleaned when scale-de¬ 
posits accumulate in them. Hence, the water- 
jackets for some small engines are made of 
sheet metal, as shown in Fig. 183. The water- 
jacket, shown at a, surrounding the cylinder b, 
is made of heavy sheet copper held in place, 
Avithout gaskets, by means of the bolts c at one 
end and the right-and-left nipple d at the other 



Fig. 183 


end. A compression relief cock e, operated by 
means of a hand wheel on a rod extending out¬ 
wards from the cock to a point outside the 
frame, is provided for reducing the compres¬ 
sion pressure to facilitate starting. The water- 
jacket may be drained through a drain cock f 
screwed into a boss brazed to the outside of the 
jacket. Water-jackets of this type can be re¬ 
moved from the cylinder when it becomes nec¬ 
essary to clean them or when repairs to the 





























































The Automobile Handbook 


423 


cylinder make it desirable. The cylinder shown 
in Fig. 183 is of the automobile type. 

The thickness of the water-jacket space 
around the cylinder of an explosive motor 
should not be less than one-eighth of the bore 
of the cylinder, while the water space surround¬ 
ing the head combustion chamber of the cylin¬ 
der should not be less than one-sixth of the cyl- 
inder bore. 

Bosses for pipe connections to the water- 
jacket outlet should always be placed at the 
highest point of the jacket, so as to prevent an 
air space being formed above the outlet of the 
jacket. Steam will be formed in this space, and 
with a gravity or thermal-siphon system is lia¬ 
ble to blow, or force the water out of the cylin¬ 
der jacket. 

To obtain the greatest degree of fuel econ¬ 
omy and motor efficiency the jacket water 
should be always of a temperature slightly un¬ 
der the boiling point of water. A cool water- 
jacket is a sign of an inefficient motor. 

Water-jacket, Leaks in. A leak in the wa¬ 
ter-jacket of the cylinder of a gasoline motor 
may be due to one of two causes: Either to 
spongy places in the metal of the jacket from 
imperfect foundry work, or to cracks in the 
jacket from allowing the water to stay in the 
cylinder jacket during extremely cold weather, 
and the car not in use. The spongy place or 
crack may be repaired by using one of the two 
following solutions: Remove the cylinder from 


424 


The Automobile Handbook 


the motor and first wash out the inside of the 
jacket with a 20 per cent solution of sulphuric 
acid and water, taking care, however, not to 
let any of the solution get on any of the fin¬ 
ished parts of the cylinder. For a spongy place 
in the jacket use a saturated solution of sal- 
ammoniac, and place the cylinder in such a posi¬ 
tion that the spongy place is underneath; allow 
to stand in this position for at least two or three 
days. Then empty out the solution and leave 
the cylinder standing for two or three days 
more, until the leak has thoroughly rusted. For 
a cracked water-jacket, keep the water-jacket 
full of a saturated solution of sulphate of cop¬ 
per (blue vitriol) for at least four days. The 
crack is filled up by what is practically an elec¬ 
tro-chemical deposit of pure metallic copper. 

Joint—Universal. The elementary form of a 
universal-joint or flexible coupling consists of a 
spiral spring. Such a form of universal-joint is 
sometimes used to drive a rotary pump, or a 
small generator on a car. The rear wheels or 
axle of a car are sometimes driven by means of 
a longitudinal shaft with a quarter-turn drive 
on a counter shaft, or a bevel gear drive at¬ 
tached to the differential gear of the rear axle. 
In such cases some form of universal-joint is 
necessary to allow the rear wheels and axle to 
accommodate themselves to the inequalities of 
the road surface. Three forms of universal- 
joints are shown in Figure 184. The upper view 
in the drawings shows the form most generally 


The Automobile Handbook 


425 




































































































































426 The Automobile Handbook 

used on motor-cars, for the purposes just de¬ 
scribed. The one shown in the center view will 
allow a greater amount of angular distortion 
than the form shown in the upper view, but is 
of a more expensive construction. Where only 
a slight amount of angular distortion is needed, 
the construction shown in the lower figure in 
the drawing is very suitable, the two jaws or 



knuckles of the joint being flexibly attached 
by means of a plate of spring steel in the form 
of a cross. 

Jump Spark Ignition. In the diagram, Fig. 
185, are shown the essential elements of a jump- 
spark system of ignition. Here a is the battery, 
b is a switch for opening the primary circuit 
when it is not in use, and c is a revolving 
timer turning at one-half the speed of the 








































The Automobile Handbook 


427 


crank-shaft, if the engine is of the four-cycle 
type. The timer in the elementary apparatus 
shown consists of an insulating ring d mounted 
on the shaft and having dovetailed into it a 
copper or brass segment e, in electrical connec¬ 
tion, by a screw or otherwise, with the shaft f. 
A plate g is mounted loosely on the shaft, so 
that it does not turn with it, but may be rocked 
about it through a suitable arc, say 45°. 



Fig. 186 

Kalamazoo Carburetor 


Mounted on this plate, and insulated from it, 
is a brush h, that bears against the insulating 
ring and makes contact with the metal seg¬ 
ment at each revolution of the latter. The pri¬ 
mary winding of the spark coil is represented 
by i, and j is the ground on the engine. A trem¬ 
bler, k, similar to an electric buzzer, is pro¬ 
vided so that the current may be rapidly inter¬ 
rupted. 

A full description of the construction and 






































428 


The Automobile Handbook 


operation of the jump spark coil is given in tk/? 
section on electric ignition. 

Kalamazoo Carbureter. Fig. 186 shows a sec¬ 
tional view of this carbureter, the operation of 
which is as follows : 

First, the concentric float A has a brass tube 
B inserted in its hub part, which guides it on 
the central part of the float chamber, and 
through the top of the float valve D for con¬ 
trolling the entrance of gasoline into the float 
chamber. Second, the connecting pin operates 
in a slotted portion of the float chamber hub. 
Air enters by the opening F, and mixture es¬ 
capes through the passage G, both controlled 
by butterfly valve H, one for regulating the 
supply of air, so that on cold mornings the air 
supply is limited, and a richer mixture obtained 
because of the greater pull on the gasoline, and 
the more of it that is drawn. Third, the needle 
valve K is novel in that it is termed an air lift 

svstem. The valve has its lower end within a 
«/ 

well part of the nozzle, the well being on a 
level with the gasoline level in the float cham¬ 
ber. The valve K is hollow for admitting air 
from the outside, so that with a heavy motor 
pull the air is drawn through the valve, as in¬ 
dicated by the arrows, and rises through the 
gasoline in the well, lifting it with it and carry¬ 
ing it into the mixing chamber. The valve is 
adjustable, and can be set to give a suitable mix¬ 
ture for the varying motor speeds. 

Kerosene as a Fuel. Kerosene has been used 


The Automobile Handbook 


429 


as an explosive power, and crude petroleum is 
gaining favor as an efficient liquid fuel. With 
a specific gravity varying from 0.78 to 0.82, 
and a vapor flashing point at 120 to 125 de¬ 
grees Fahr., kerosene ignites at 135 degrees 
Fahr., and boils at 400 degrees Fahr. Its vapor 
is five' times heavier than air, and requires 76 
cubic feet of air to one cubic foot of vapor for 



Fig. 187 


its combustion, giving 22,000 heat units per 
pound, or 4,000 more than gasoline. 

Kerosene as a Cleansing Agent. Kerosene 
injected into a motor cylinder and allowed to 
remain over night will remove all deposit from 
the piston head. It should then be blown out 
through the relief-cock or the exhaust-valve. 

Kerosene is also used to remove the gummy 
residue left on the piston and the cylinder wall 
by the lubricating oil. When injected into the 














430 The Automobile Handbook 

cylinder in the manner above described, it. 
facilitates the starting of the'motor, if it lias 
been standing idle for any length of time. 

Figure 187 shows a form of kerosene cup 
which may be permanently attached to the mo¬ 
tor. After removing the cap, the cup is filled 
and tlie kerosene admitted to the motor cylin¬ 
der by depressing the valve-stem. 



Fig. 188 

Kingston Carburetor 


Key—Inlet or Exhaust-Valve. Trouble from 
a broken inlet-valve stem, or key is more likely 
to occur with automatic valves than with those 
mechanically operated. The result, if the valve 
opens downwards, is to let it stay open all the 
time, causing that cylinder to cease work, while 
the sparks from the plug ignite the mixture in 
the intake pipe, and cause explosions there and 































The Automobile Handbook 


431 


in the carbureter. If the valve, whether auto¬ 
matic or mechanically operated, opens up¬ 
wards, it will clatter on its seat and permit 
much of the mixture to be expelled during the 
first part of the compression stroke. 

Valve-stem keys should be made of annealed 
tool steel, and should not be made too close a 
fit in the valve-stem slot, because they are likely 
to bend slightly in use. Ordinarily it is cheaper 
to buy these keys of the maker of the car than 
to make them specially. One or two spare keys 
should always be carried. 

Kingston Carbureter. The Kingston carbu¬ 
reter, Fig. 188, uses a ball type of auxiliary 
air valve instead of the employment of spring 
control dashpot, diaphragm or auxiliary air 
valve. The main air intake A communicates 
with the vertical mixing chamber B, in which 
the sides C are beveled outward, giving a center 
tube effect, so that the air current converges 
above the nozzle N, as indicated by the arrows. 
I) marks the exit to the motor controlled by the 
butterfly throttle E. Auxiliary air enters 
through five circular openings G, arranged in 
a semi-circle in the floor of an extension H of 
the mixing chamber. Each of these five open¬ 
ings consists of a bushing K threaded into the 
opening in the extension II, and having its top 
beveled to receive a five-eighths inch bell metal 
bronze ball L, which is retained in position by 
a threaded bushing M, fitting in the top of the 
extension H. It has a pair of downward project- 


432 


The Automobile Handbook 


ing hooks N for preventing the ball getting out 
of position, but not interfering with the ball 
rising.vertically when forced to do so by the 
pull of the motor, at which time additional air 
is admitted. Two others of the five auxiliary 
entrances are shown at I and O, all of the five 
containing balls of the same size and weight. 
The air entering through the openings guarded 
by these balls has an unrestricted passage into 
the mixing chamber and thence to the motor. 

9 

Any ball is easily moved by unthreading the 
cap M, after which the ball can be lifted out. 

The gasoline enters the carbureter from 
the gasoline tank by way of the connec¬ 
tion J, which is guarded by the needle valve 1\. 
operated through the lever S, pivoted in the 
side of the casting and with its long arm bear¬ 
ing on the top of the cork float. The float is 
fitted with a metal bushing. Complete control 
of the nozzle N is through the needle valve V, 
which, at the top of the carbureter, has a T- 
piece X, by which it can be raised or lowered, 
thereby regulating the flow of gasoline. A 
feature of the throttle connection T is the ser¬ 
rated lower face of its hub W, so that by loos¬ 
ening a lock nut Z, the handle T may be turned 
in any direction most convenient. The air in¬ 
take A consists of an L-shaped piece secured 
to the carbureter casting bv a nut P, and in the 
base of this is a circle of openings F where cur¬ 
rents of air can enter, the object of these open¬ 
ings being that by priming the carbureter, and 


The Automobile Handbook 


433 


overflowing: the open mouth of nozzle N the 
gasoline falls to the vicinity of the holes F, and 
the air entering through these openings will 
facilitate the breaking up of the gasoline, and 
thereby assist the starting of the motor. 

Knocking—Locating Cause of. Tracing a 
knock is sometimes a puzzling job. It may be 
in one of the main bearings of the engine, in 
the camshaft bearings, in a loose valve lifter, 
in a loose camshaft gear key, in a loose pump 
or magneto drive coupling, an unsuspected 
loose bolt between two parts supposed to be 
fast, or in any of a dozen, or score of other un¬ 
suspected places. A valuable aid in locating a 
mysterious knock is a flexible speaking tube 
such as is used with phonographs. One end of 
such a tube can be held to the ear and the 
other moved about from point to point until 
the exact spot is found where the noise is loud¬ 
est. Another aid is a light bar of iron, one end 
of which is pressed against the part where the 
knock is suspected and the other touched to the 
forehead or the teeth, when the sound is clearly 
transmitted. 

Knocking or pounding is an inevitable warn¬ 
ing that something is wrong with a motor. It 
may be due to any of the following causes: 

Premature ignition : The sound produced by 
premature ignition may be described as a deep, 
heavy pound. 

Using a poor grade of lubricating oil will 
cause premature ignition. The carbon from the 


434 


The Automobile Handbook 


oil will deposit on the head of the piston in 
cakes and lumps, and will not only increase the 
compression, but will get hot after running a 
short time and will ignite the charge too early, 
and thereby produce the same effect as advanc¬ 
ing the spark too much. If this is the cause the 
pounding will cease as soon as the carbon de¬ 
posit is removed from the combustion chamber. 

Badly worn or broken piston-rings. 

Improper valve seating. 

A badly worn piston. 

Piston striking some projecting point in the 
combustion chamber. 

A loose wrist-pin in the piston. 

A loose journal-box cap or lock-nut. 

A broken spoke or web in the flywheel. 

Flywheel loose on its shaft. 

If the spark plug be placed so as to be ex¬ 
actly in the center of the combustion space, an 
objectionable knock occurs, which has never 
been fully explained. In some motors it ren¬ 
ders a particular position of the spark control 
lever unusable; this form of knock disappears 
either on making a slight advance or retarda¬ 
tion of the ignition. 

Explosions occurring during the exhaust or 
admission stroke. This is almost always due to 
a previous misfire, and it is prevented by stop¬ 
ping the misfires. 

If the ignition is so timed that the gases reach 
their full explosion pressure during the com¬ 
pression stroke, that is, if the spark be unduly 


The Automobile Handbook 


435 


advanced when the motor is not running at a 
high speed, an ugly knock occurs, and great 
pressure is developed on the crank-pin bearing, 
wrist-pin, and connecting rod. The result may 
be the bending or distorting of the connecting 
rod. 

The crank-pin may not be at right angles to 
the connecting rod. This cause of knock is 
often hard to find. 



The chain may perhaps be loose. This pro¬ 
duces a blow if the chain should jump one of 
the sprocket teeth. The noise is not usually 
called a knock because it does not recur at uni¬ 
form intervals. It is dangerous to run with a 
loose chain, as breakage might precipitate a 
car down a hill backwards. 

t 

The bearings at either end of the connecting 



































436 


The Automobile Handbook 


rod may be loose. A knock during the explo¬ 
sion stroke, and also at each reversal of the 
direction of the piston. 

If the crank shaft is not perfectly at right 
angles to the connecting rod, the crank shaft 
and flywheel will .travel sideways so as to strike 
the crank shaft bearings on one side or the 
other. 



fi] 



1 1 



1 1 



S’ 

( 

1*11 


{Q) i 


KNUCKLE 

: JOINT 


Fig. 190 


Knuckle Joints. Swivel or knuckle-jo'ints 
for connecting the steering arm of the wheel, or 
Irver steering mechanism to the arms on the 
knuckle-joints of the steering wheels are of va¬ 
rious forms. Figures 189 and 190 show knuckle- 
joints which may be used for the above pur¬ 
pose. They are of simple construction and 
practically inexpensive to make. They may be 
used with any standard drop-forged jaw-ends. 

Komet High Tension Magneto. The Komet 






























The Automobile Handbook 


437 


high-tension magneto, Fig. 191, combines the 
primary and secondary windings on the arma¬ 
ture, so that no coil is required. The field con¬ 
sists of three permanent magnets secured to a 
bronze base. The make-and-break device is 



operated by the armature, which latter is pro¬ 
vided with a steel collar having two spurs upon 
it, at 180 degrees from each other. These rub 
against a block fastened to the breaker arm 
and separate the platinum point on this arm 
from a stationary platinum button. A curved 







































































































438 


The Automobile Handbook 


spring holds the arm in contact when not ac¬ 
tuated by the spurred collar. The distributer 
is fitted above the make-and-break, and consists 
of a circular vulcanite block having a brass arm 
and spring pressed carbon brush, which makes 
contact with four or six brass blocks in the vul¬ 
canite casing enclosing the distribution mechan¬ 
ism. 

Krebs Carbureter. In the Krebs style of car¬ 
bureter, a constant proportion of gasoline and 
air is maintained by means of suitable sections 
of air and gasoline outlets. The openings are 
so arranged that a proper mixture is main¬ 
tained at minimum suctions, after which grad¬ 
ually increasing quantities of supplementary 
air are admitted. 

A number of attempts have been made to im¬ 
prove upon the Krebs principle by variously 
shaping the supplementary air openings, or the 
spring on the supplementary air valves, so as 
to insure complete compensation for the in¬ 
crease in richness of the mixture formed in the 
spray chamber with increasing suction, by the 
addition of the correct amount of supplemen¬ 
tary air at all suctions. The mixture formed in 
an ordinary spray carbureter becomes richer as 
the suction increases. At first the only means 
provided to correct this defect was a hand-regu¬ 
lated air valve; but since the advent of the 
Krebs carbureter, practically all new carburet¬ 
ers brought out have some arrangement for au¬ 
tomatically keeping the mixture constant, re- 


The Automobile Handbook 


439 


gardless of variations in suction. In general 
the means provided are close copies of the 
Krebs supplementary air valve, though in some 
instances this valve, instead of being actuated 
by the suction, is operated either hydraulically 
by means of a diaphragm in a chamber commu¬ 
nicating with the water cooling system, or me¬ 
chanically by direct connection with the throt¬ 
tle valve. 

Krouse Carbureter. The Krouse carbureter 
has eleven spraying nozzles, which can be 
brought into use, one at a time until all are 
emitting gasoline. This carbureter resembles 
a drum placed on end. The drum is nearly all 
float chamber, with a concentric air chamber 
surrounding the float chamber. The top of the 
float chamber is fitted with eleven standpipes, 
the bottoms of which conduct the gasoline into 
the float chamber. These eleven nozzles form a 
semi-circle, and immediately above them is a 
metal semi-circle which can be revolved so as to 
cover any number, or all of the nozzles, thus 
shutting them off entirely. Around each noz¬ 
zle is a small air vent, to allow the air to rise 
past the mouth of the nozzle, and mix with the 
gasoline. There are no springs, and the only 
moving part is the throttle, which is the metal 
semi-circle before mentioned, and which effect¬ 
ually shuts off gasoline and air, one nozzle at 
a time. 

Lamps. It goes without saying that the burn¬ 
ers should be kept clear, wires being passed 


440 


The Automobile Handbook 


through the gas apertures and the air apertures 
at intervals. The burners should be unscrewed 
occasionally and blown through, and- the inte¬ 
rior of the burner body scraped clean of de¬ 
posit. Outside of keeping the lenses and 
glasses bright, and polishing the exterior of the 
lamp, there need be no other attention paid ex¬ 
cept to keep all joints and the bracket screws 
or nuts tight. 

By far the best and handiest thing to clean 
the lens mirrors is a mixture of equal parts al¬ 
cohol and water. Denatured alcohol answers 
the purpose perfectly well. Pure alcohol evap¬ 
orates so quickly that it leaves the greasy film 
pretty much as it was, whereas a 50 per cent 
solution evaporates more slowly and gives time 
to wipe the glass clean. It would be an excel¬ 
lent idea for every garage to keep a bottle of 
this solution and some clean rags always on 
hand. While on the subject of lamps it is worth 
mentioning that all gas tubing from a genera¬ 
tor should slope either downward, or away from 
the generator, and there should be provi¬ 
sion for draining it at its lowest point, since 
there is a gradual condensation of water in the 
piping which, if it collects in pockets, results in 
objectionable flickering. 

The Condenser. When used at all, the con¬ 
denser or its substitute is put off in some po¬ 
sition where it becomes caked with mud and is 
almost forgotten until it is full and the lamps 
begin to flicker. Then the mud is cleaned from 


The Automobile Handbook 


441 


it and it is drained out. It should be placed so 
that it is close to the lamps, where it will catch 
all of the condensation from the gas going to the 
burners, and in addition any water that may en¬ 
ter the burners due to washing of the car. It 
should be emptied from time to time, say once 
or even twice a month, when the lamps are in 
regular use. The majority of troubles with acet¬ 
ylene lamps are due to lack of a condenser, and 
to the use of too small metal tubing. 

Leakage — of Current. Sufficient leakage of 
current to make trouble—but not enough to be 
observed without testing with a magneto—may 
be due to moisture in the mica insulation of the 
insulated electrode, or to a bridge of carbon. 
Wh en it is suspected that the trouble is due to 
either of these causes, it is a good plan to dry 
out the insulation thoroughly and clean the 
lower end with a brush or piece of waste and 
a little gasoline. 

These troubles are more liable to occur when 

i 

the batteries have become weak from use, or so 
far exhausted that they will not give sufficient 
current for ignition. 

Leakage op Water or Gasoline. This is 
usually due to carelessness, and indicates a 
slovenly operator. The loss of water, if small, 
may be left till the run is completed. A leakage 
of gasoline is far too dangerous to leave alone 
under any circumstances. A common cause is a 
minute hole in the float of the carbureter, 
causing it to flood. The hole can be found by 


442 


The Automobile Handbook 


putting the float into boiling water and watch¬ 
ing for bubbles. Leaky joints in gasoline or 
water pipes may be made tight by means of 
coarse linen or canvas, covered with a paste of 
litharge and glycerine. This should be again 
covered with a bandage of adhesive or sticky 
tape, such as is used for electrical purposes. 

Learning to Operate a Car. Learn to distin¬ 
guish normal sound of the motor and its valves, 
from the following: 

Knocking which may be due to a worn or 
loose bearing. 

The absence of explosion in one of the cylin¬ 
ders. 

A hissing noise due to leakage of the com¬ 
pression. 

A sharp spitting due to leakage during the 
explosion stroke. 

Any pounding of the admission-valve on its 
seat. 

Any racing of the motor. 

The sound of an unoiled or dry bearing. 

The rattle of a part becoming loose. 

Owing to the value of the indications from 
the above, it is important that no oil-cans, span¬ 
ners, or other tools, should be left loose in the 
car. 

A little practice will enable the operator to 
distinguish the beat of the motor, and the vibra¬ 
tion due to the springs, from the jumping, due 
to road surface, so as to note at once: 

A broken gear tooth. 


The Automobile Handbook 


443 


A loose chain. 

A deflated or punctured tire. 

A broken spring. 

Ineffectual explosions due to poor compres¬ 
sion. 

Backlash in steering gear. 

Lehman Distributer. Fig. 192 shows the 
Lehman distributer for four and six-cylinder 



Fig. 192 

Lehmann Distributer 


cars. The body A has bolted to it a hard rub¬ 
ber insulation B, which is grooved to receive 
the similar insulation C, and coned to take the 
vulcanite cone part D, which revolves with the 
shaft S. This shaft D is a continuation of shaft 
E, but of smaller diameter, the larger diameter 
part being supported on a double race of ball 
bearings. Secured to the vulcanite cone F is a 
































444 


The Automobile Handbook 


distributing disc G, and attached to the under 
surface of C is a collecting disc. The rotating 
disc G wipes the ends of the terminals H. The 
timer portion K is of regular construction as 
used in the Lehman timer. For the purpose of 
taking off the ground wire a small ball L is held 
against shaft S, through spring M, and a spring 
connection N couples for the wire. In attach¬ 
ing this distributer to its shaft the usual method 



of keying, or pinning is dispensed with, and re¬ 
course is had to a split cone O, which fits within 
tin* tapered bored end of shaft E. A jam nut P 
serves to anchor the split cone 0 to the drive 
shaft. 

Locking Devices, for Bolts and Nuts. All 

bolts and nuts upon a motor car which are not 
provided with locking devices should be in¬ 
spected at frequent intervals and tightened if 
necessary. The vibration and jars to which a * 




































The Automobile Handbook 


±45 


motor car is subject have an astonishing way of 
loosening bolts and nuts. Figures 193 and 194 il¬ 
lustrate six different methods of preventing 
bolts and nuts from becoming loose. 

A—A lock-nut, which should be a size smaller 
than the nut proper, as shown in the drawing. 

B—A headless set screw, tapped into the part 
which receives the bolt. 

C—A spring washer under the nut. 



D—A split pin through both bolt and nut. 

E—A split pin through the bolt only, but fit¬ 
ting in half-round grooves in the nut. 

F—A nut-lock with holding down screw. 

Loose Connections. These occur in the most 
peculiar places. Sometimes a platinum tip gets 
free from its carrying screw, sometimes a lead 
lug breaks inside a storage battery cell. Some¬ 
times a disconnection occurs by breakage of a 
copper wire inside its unbroken cover. 





































446 


The Automobile Handbook 


Lubrication. To ensure easy running, and 
reduce the element of friction to a minimum it 
is absolutely necessary that all surfaces rubbing 
together should be supplied with oil or lubri¬ 
cating grease, but it is also a fact, not so well 
understood, that different kinds of lubricant 
are necessary to the different parts or mechan¬ 
isms of a motor car. 

As the cylinder of an explosive motor oper¬ 
ates under a far higher temperature than is 
possible in a steam engine, consequently the oil 
intended for use in the motor cylinders must 
be of such quality that the point at which it will 
burn or carbonize from heat is as high as possi¬ 
ble. 

While a number of animal and vegetable oils 
have a flashing point, and yield a fire test suf¬ 
ficiently high to come within the above require¬ 
ments, they all contain acids or other sub¬ 
stances which have a harmful effect on the 
metal surfaces it is intended to lubricate. 

Lubricating. Oils. The qualities essential in 
a lubricating oil for use in motor cylinders in¬ 
clude a flashing point of not less than 500 de¬ 
grees Fahrenheit, and fire test of at least 600 
degrees, together with a specific gravity of 25,8. 

At 350 to 400 degrees Fahrenheit, lubricating 
oils are as fluid as kerosene, therefore the ad¬ 
justment of the feed should be made when the 
lubricator and its contents are at their normal 
heat, which depends on its location in the car. 
Steam engine oils are unsuitable for the dry 


/ 


The Automobile Handbook 447 

heat of motor cylinders in which they are de¬ 
composed whilst the tar is deposited. 

All oils will carbonize at 500 to 600 degrees 
Fahrenheit, but graphite is not affected by 
over 2,000 degrees Fahrenheit, which is the ap¬ 
proximate temperature of the burning gases in 
an explosive motor. The cylinder of these mo¬ 
tors may attain an average temperature of 300 
to 400 degrees Fahrenheit. So that graphite 
would be very useful if it could be introduced 
into the motor cylinder without danger of clog¬ 
ging the valves, and could be fed uniformly. 
These difficulties have not yet been overcome. 
Graphite is chiefly useful for plain-bearings and 
chains. 

The film of oil between a shaft and its bear¬ 
ing is under a pressure corresponding to the 
load on the bearing, and is drawn in against 
that pressure by the shaft. It might not be 
thought possible that the velocity of the shaft 
and the adhesion of the oil to the shaft could 
produce a sufficient pressure to support a heavy 
load, but the fact may be verified by drilling a 
hole in the bearing and attaching a pressure 
gauge. 

Roller and ball-bearings provide spaces, in 
which, if the oil used contains any element of 
an oxidizing or gumming nature, a deposit or 
an adhesive film forms upon the sides of the 
chamber, the rollers or balls, and the axle. This 
deposit will add to the friction, hence it is the 


448 


The Automobile Handbook 


more important to use a good* oil, or a petro¬ 
leum jelly in such bearings. 

Air-cooled motors, being hotter than water- 
cooled, must have a different lubricant, or one 
capable of withstanding higher temperatures. 

The effect upon animal or vegetable oils of 
such heat would be to partially decompose the 
oils into stearic acids and oleic acid and the con¬ 
version of these into pitch. Such oils are there¬ 
fore inadmissible for air-cooled motor use. 

Mineral oils are not so readily decomposed 
by heat, but at their boiling points they are 
converted into gas, and any oil, the boiling- 
point of which is in the neighborhood of the 
working temperature of the motor cylinder, is 
useless, as its body is too greatly reduced to 
leave an effective working film of oil between 
the cylinder and the motor piston. 

The essentials for the proper lubrication of 
air-cooled motors are: 

That the oil should not decompose. 

That it should not volatilize, as this will re¬ 
sult in carbon deposits. 

That its viscosity should be equal to that of 
a good steam engine oil at similar temperatures. 

That it should be fluid enough to permit of 
its easy introduction into the cylinder. 

That it will have no corrosive effect on the 
cylinders and no tendency to gum. 

That it will not oxidize with exposure to air 
and light. 

Lubrtcattnu Devices. Rome makers of verti- 


The Automobile Handbook 


449 


cal cylinder motors use the splash system, 
whereby oil fed by gravity from a tank above 
the level of the crank-ease flows into the crank¬ 
case, whence it is splashed over the piston and 
the wrist and crank-shaft bearings. The large 
end of the connecting rod, which works in the 
crank-case, is made to dip or splash into a bath 
of oil. This lubricates the crank-pin. The 
splashing is invariably utilized to lubricate the 
cylinder by wetting the bottom of the piston 



Fig. 195 


and splashing into the cylinder. A little ring is 
sometimes made in the crank-case, into which 
the oil collects and into which also the end of 
the piston dips. The oil usually requires chang¬ 
ing every 100 miles on small motors, or every 
75 miles on large. 

Figure 195 shows a vertical cylinder motor 
using splash lubrication. 

With the use of high-speed gasoline motors, 
it has been found necessary to use a forced cir¬ 
culation of the oil in order to completely lubri- 








450 


The Automobile Handbook 


cate the interior of the cylinder. The usual 
method with high-powered motors is to employ 
a belt-driven pump to force the oil through ad¬ 
justable conduits to the various moving parts. 
Such pumps, operating in ratio to the speed of 
the motor, supply lubricant more rapidly as the 
motor speed increases, and less as it decreases. 
Thus, a perfect supply is maintained, on the 
one hand, and flooding of the motor is pre¬ 
vented on the other. 

Where horizontal cylinders are used, it is 
customary to use grease cups, and to control 
the feed by mechanical or spring pressure. Such 
devices are less suitable for vertical cylinder 
motors, which require oil in large quantities 
and exact adjustment in its flow. One very use¬ 
ful feature of oil pump lubrication is, that the 
flow of oil may be kept in proportion to the 
speed of the motor. This is a very necessary 
feature, as without it flooding is liable to result. 

Lubricators. It should be ascertained from 
the maker of the car how many drops of oil 
per minute are necessary for the different mech¬ 
anisms of the car, including the motor. The 
lubricators should then be set accordingly. 

It should be remembered that in cold weather 
when the oil is thick a different adjustment of 
the lubricators will be necessary from that 
found suitable in warm weather. It is impor¬ 
tant that the lubrication should be regular, and 
good oil used, but not too much. Too much oil 
will foul the spark plugs, clog the valves, and 


The Automobile Handbook 


451 


interfere with the quality of the explosive mix¬ 
ture. For this reason the lubricators should 
always be carefully closed when the car is 
stopped. If a mechanical lubricator is used, ex¬ 
amine the mechanism sometimes, and do not 
trust entirely to the feed. If a pressure lubri¬ 
cator is used, see that the piston or cap is tight, 
for if not the pressure will stop the lubrication. 

It sometimes happens that an oil pipe or oil 



hole is stopped up and needs cleaning, or per¬ 
haps the plug at the bottom of the crank cham¬ 
ber has come unscrewed and dropped out, los¬ 
ing all the oil. The proper amount of oil in the 
crank-case is about half a pint. An extra lubri¬ 
cator leading to the cylinders and crank-case 
should be fitted, so that extra oil can be fed by 
a hand pump, if there is any doubt about the 
motor getting enough. 
































452 


The Automobile Handbook 


Figure 196 shows four forms of lubricators 
for automobile use. 

A—Plain, glass body oil cup, feeds only when 
shaft is running. 

B—Sight feed, glass body oil cup, has an 
index-arm on top which indicates whether the 
oil feed is off or on. 

C—Pressure feed, piston form of lubricator, 
for heavy bodied oil; the oil is forced into the 



Fig. 197 


bearings by means of a spring-actuated piston 
in the lubricator. 

D—Plain grease cup, oil or grease forced into 
the bearing by screwing down the cap. 

A form of pressure lubricator is illustrated in 
Figure 197, in which a slight pressure from the 
crank-case of the motor causes the oil to be 
forced through the pipes leading to the differ¬ 
ent parts of the motor. This form of pressure 
lubricator is only applicable to opposed cylin¬ 
der motors with enclosed crank-case, as shown 
in the drawing, or to vertical two-cylinder mo- 








The Automobile Handbook 


453 


tors with both pistons connected with one com¬ 
mon crank-pin. 

Force Feed Lubricators. Of all the oiling sys¬ 
tems in use, the mechanical oiler, or force, 
feed lubricator, has the largest application, and 
is generally used in connection with the splash 
system. The oiler is generally located under 
the bonnet, so that the oil in it will be of a more 
uniform temperature in both summer and win¬ 
ter, but several cars carry it upon the dash. 
When placed under the bonnet, oilers are 
usually located at the rear of the motor, but 
sometimes they may be found under the ex¬ 
haust manifold, where a hotter and more even 
temperature may be maintained. 

The method of driving mechanical oilers dif¬ 
fers in the different cars In some cases they 
are gear driven, in others an eccentric drive is 
employed, and in still other cars the belt or 
chain drive is used, although the latter method 
is being rapidly discarded. 

The number of feeds used varies on the dif¬ 
ferent cars from two to fourteen, depending 
upon the number of cylinders and bearings 
used on the engine. In a six-cylinder car, it is 
usual to find four feeds going to the crankshaft 
bearings, six to the cylinders, three to the 
crankcase compartments, and one to the fan 
bearing. 

When mechanical oilers are used for lubri¬ 
cating the motor, the crank-case is usually di¬ 
vided into partitions, most of them dividing it 


454 


The Automobile Handbook 


into halves, one compartment for the two front 
cylinders and the other for the two rear cylin¬ 
ders. Sometimes three partitions, giving four 
compartments, are used. This arrangement 
gives one portion for each connecting rod. 






ZJ 

o 

o 

a 

a 

W 


When this construction is used, the center par¬ 
tition will be found higher than the other two. 

A force feed lubricator usually consists of 
an oil tank through which passes a shaft, which 
has a slow, but constant motion through me- 
































































































The Automobile Handbook 


455 


chanical connection with the engine. This shaft 
successively operates by means of cams, or oth¬ 
erwise, a series of small piston pumps, usually 
submerged in the oil, each pump feeding an oil 
tube. The piston displacement of each pump 
may be adjusted independently by changing the 
length of stroke so that any amount of oil de¬ 
sired may be delivered. Each pump stroke cor¬ 
responds with a definite number of engine 
strokes. 

In some systems of force feed lubrication the 
oilers are made without valves, double plungers 
being used to force oil to the sight feeds, and 
drawing positively from the sight feed and 
forcing to the delivery points. 

The Hancock lubricator, Fig. 198, is of this 
type, and action is as follows: Worm A drives 
worm gear B and the shaft to which it is at¬ 
tached. On this shaft are two eccentrics C 
which impart a reciprocating motion to rod D 
carrying rocker arms E. and E'. To one end 
of these arms are fastened pistons F, and F'. 
The crank G is secured to the taper shaft H, 
and through connecting rod J a rocking mo¬ 
tion is transmitted. This taper shaft TI is pro¬ 
vided with holes K, which on the suction stroke 
register with the openings L, and L', and the 
pistons, and on the forcing stroke with open¬ 
ings M, M, and the pistons. The arrows indi¬ 
cate the direction of flow of the oil to delivery 
points, the quantity being regulated by con¬ 
trolling the stroke of piston F through the lost 


456 


The Automobile Handbook 


motion allowed between the stop rod L and reg¬ 
ulating piece O. P is the regulating screw, pro¬ 
vided with a projection Q, which fits firmly into 
the upper end of piece 0, forming a positive 
locking device. Shaft H is equipped at one 
end with a spring R which holds it to its seat. 



At the other end, washer S and two lock-nuts T 
and T' hold the- shaft in its correct position. 
The shaft is thus allowed to run free in its gear, 
requiring but little power. Any number of 
feeds from one to sixteen may be used to work 
against pressure. In the Lavigne mechanical 
oiler, Fig. 199, the pumps are without check 

































































The Automobile Handbook 


457 


valves, or springs of any kind. The plungers 
P, are raised and lowered by arms A attached 
to the drive shaft. On the up stroke a certain 
quantity of oil is drawn into each pump cylin¬ 
der, and on the down stroke this quantity is dis¬ 
charged. 

At the base of each plunger is an oscillating 
valve V, which, as illustrated, has the opening 
O ready for the up stroke, so that oil may be 
drawn from the reservoir into the plunger. Be¬ 
fore the down stroke begins, the valve is oscil¬ 
lated by a cam device so that the entrance O is 
closed and the oil is directed through the lead 
L, which connects with the bearings. There is 
a time when the plunger L, is stationary at the 
top, and also at the bottom of the stroke, which 
is achieved by the cross head IT, which raises 
and lowers the plunger. This cross head slides 
on the plunger until it contacts with a lower 
shoulder S and an upper one T. And during 
the period of no movement of the plunger the 
valve V is being oscillated to be ready to open 
the entrance O for intake stroke, and another 
passage for the expulsion stroke. 

The Pierce-Arrow oiling system, Fig. 200, is 
partly positive, and partly gravity. The oil 
pump is positively driven from the engine, and 
pumps the oil from the crank chamber up into 
the reservoir located on the engine. Pipes lead 
from this reservoir to every crankshaft bear¬ 
ing, the flow to the bearings being by gravity 
under a head of twelve inches, which corre- 


458 


The Automobile Handbook 


sponds to a pressure of about six ounces. The 
crankshaft bearings are drilled hollow, and in 
this way the crankpins and large ends of the 
connecting rods are lubricated. A gauge is 
usually placed on the dash to indicate the quan¬ 
tity of oil in the reservoir. 

The Pierce system does not allow any oil to 
remain in the crankcase, the oil flying off the 



Fig. 200 

Pierce-Arrow Oiling Svstem 

O 


crankpins being sufficient to lubricate the cylin¬ 
ders. As there is always a mist of oil flying 
around in the crankcase, it is known as the 
“mist” system. 

As shown in Fig. 200, the oil supply is car¬ 
ried in a sump S' beneath the crankcase, and 
the crankcase bottom is sloped towards the 
center so that oil falling in it is immediately 












































































The Automobile Handbook 


459 


drained into the sump. The gear pump P, 
driven from the camshaft through a vertical 
shaft, elevates the oil to a tank T carried above 
the cylinder heads, and from this a lead L 
passes direct to each of the crankshaft bearings. 
From these bearings the oil passes through the 
drilled crankshaft to the lower bearings of the 
connecting rods, whence any overflow falls into 
the crankcase, or is thrown into the cylinders 
in the form of a mist through the slot in the 
baffle plate, closing the lower end of the cylin¬ 
der to prevent an excess of oil getting on the 
walls. This mist not only cares for the cylin¬ 
der walls, but also oils the wrist-pin bearing. 
The flow of the oil through the leads L from the 
tank to the bearings is regulated by thimbles 
M, inserted in the upper ends of the leads where 
they enter the oil tank, and in each thimble is 
a small opening which allows only a limited 
amount of oil to flow. The size of the openings 
in the thimbles is varied to suit the demand of 
the bearings for oil. 

Flywheel Oiling Systems. In the Ford fly¬ 
wheel system of oiling illustrated in Fig. 201, 
the flywheel casing serves as an oil reservoir, 
and the rotation of the wheel throws the oil up 

\ 

into pockets, from whence it is conducted 
through pipes to the crank-case. The angle of 
the pipes is such that even on extreme grades 
there is sufficient drop to insure a flow of oil. 
A depression M is found in the crank case be¬ 
neath each connecting rod, in order to limit 


460 


The Automobile Handbook 


the amount of oil carried in the crank case, and 
also to insure an even level of oil within the 


case. 

Royal Tourist Double System. Two entirely 
separate methods of lubrication are used in this 


rf 



Who 

■HO 


d 

vy 

<i 

\\ 

c 

] 



„ v c 

i 

9 L 

s 

Jf rn- 

yf /A 

ijj 



p 


— 






it- 


>- 



system, both being mechanically operated. The 
two methods are, the mechanical oil feed to 
main bearings and constant level oil splash, 
arid sump and pump system. In the first, a 
mechanical oiler A, Fie. 202. is located under- 





























































The Automobile Handbook 


461 


neath the clash, so that its sight feeds may be 
seen where the dash joins the foot boards. This 
oiler draws its supply from a three gallon tank 
T, located under the front door boards, and de¬ 
livers it through leads to the three bearings B 
of the crank shaft. The crank case has a hori¬ 
zontal partition forming an oil reservoir R, and 
leaving the upper compartment C, into which 



Fig. 202 

Royal Tourist Double Lubricating System 


the connecting rods dip in the oil level it car¬ 
ries. The oil level in compartment C is equal¬ 
ized by three transverse ribs R, and the oil is 
prevented from getting above a certain level 
by holes D in standpipes, through which the oil 
overflows into reservoir R. 

In the second system a small gear pump G 
in the reservoir R discharges upwards along its 












































































462 


The Automobile Handbook 


driveshaft to an oil pipe H, which has a branch 
running to the inner end of each crankshaft 
bearing. By means of holes drilled in the bush¬ 
ings the oil is squirted into oil catches, J, J, J, 
J, that revolve with the crankshaft and feed 
the oil through holes drilled in the crankpins 
to the lower connecting rod bearings. In ad¬ 
dition the catches J receive the overflow oil, 
which works from the main crankshaft bear¬ 
ings. From the gear pump a lead K passes 
through a sight feed L on the dash, and thence 
leads to the compartment housing the half-time 
gears at the front end of the motor. A ring is 
fitted on the bottom end of the piston to pre¬ 
vent an excess of the oil from the cylinders. In 
oiling the wristpins, which are tubular, the ends 
are plugged, and the hollow thus formed re¬ 
ceives oil from a recess cut in the outer wall of 
the piston at this point, which oil feeds to the 
bearing, which is in addition to all pumped up 
through tubes in the connecting rods. 

Winton Double Pump Oiling System. The 
six-cylinder motors used on the Winton cars 
are lubricated by a double pump method, the 
pumps being driven by an eccentric off the end 
of the crankshaft. The usual sump is replaced 
by a tank. As shown in Fig. 203, one pump P 
draws the oil from a tank r f by lead L and 
forces oil to all of the crankshaft bearings, to 
the timing gear-case, and a sight feed S on the 
dash, the oil going from the pump through one 
lead N to a distributing manifold M at the 


The Automobile Handbook 


463 


side of the motor. The other pump P delivers 
this oil back to tank T, from which it was first 
drawn, thus causing a constant circulation of 
oil. 

The main oil reservoir is located on the left 
side of the motor base, and the surplus from 
the crankshaft bearings falls into the splash, 
which, instead of being allowed to increase, is 
drained off by a collector tube H to an oil well 
W, from which it is drawn by the pump P, and 
returns to the tank T. With this system the 



Fig. 203 

Winton Double Pump Lubricating System 


crankcase is comparatively dry; the lower con¬ 
necting rod bearings are oiled by drilling the 
crankshaft and the cylinder walls and upper 
wrist pins by the splash from the overflow of 
the connecting rods and what oil may be picked 
up from the crankcase. A strainer in tank T 
is used to strain all the returned oil before it is 
used again. 

Drilling Oil Passages in the Crank Shaft. 
Figs. 204 and 205 show two different methods 
of drilling the crankshaft to convey the oil to 































































464 


The Automobile Handbook 


the crankpins, and it will be noticed that the 
oil holes discharge at the highest point of the 
revolution, corresponding to the position of the 
piston at the beginning of the power or tiring 
stroke. The supply is received by the main 
bearings from the oil pump and the oil hole in 
the shaft, coinciding with that from the oiler 
has a little oil forced in each revolution and, 
generating centrifugal force throws it rapidly 
through the passages. The majority of modern 
motors are equipped with splash lubrication 
and have the connecting rods dip into the oil 



Fig. 204 


each revolution and splash it all over the inside 
of the crankcase. Some types are equipped 
with a scoop pointing in the direction of rota¬ 
tion, at the lower end of a passage connecting 
with the crank pin. The oil is sent into these 
passages with considerable force, owing to 
speed of rotation, thus assuring sufficient oil to 
the connecting rod bearings. 

This is worked to the ends of the bearing and 
thrown off in the shape of a fine mist that pen¬ 
etrates to every part of the crankcase. The oil 
splashed onto the lower cylinder walls and not 





























The Automobile Handbook 


465 


carried up by the piston is caught in little 
troughs, cast in the crankcase and drilled so 
that the oil runs down to the main bearings. 
In addition to the pipe from the oiler, the bet¬ 
ter designs provide an oil wick, or an oil ring 
or chain, all types carrying oil from a shallow 
pocket corded in the bearing cap, the wick by 
capillary attraction, and the ring or chain, re¬ 
volving with the shaft, their lower ends im¬ 
mersed in the oil will carry up a considerable 
quantity that will spread over the shaft. This' 



Fig. 205 


oil ring system is used very successfully in elec¬ 
trical machinery. With a splash lubrication it 
is advisable to drain the crankcase at frequent 
intervals, and also to put in a fresh supply of 
oil. 

Lubrication of Gears and Clutches. The 
modern ball-bearing gear box requires but lit¬ 
tle attention. Periodic filling with suitable lub¬ 
ricants is sufficient. On chain-driven cars the 
gears and differential are usually exposed by 
lifting one cover. On shaft-driven cars the 














































466 


The Automobile Handbook 


differential and rear axle system requires a cer¬ 
tain amount of attention, as too much oil in the 
differential is liable to leak through the axle 
sleeve and hub, usually getting on the brake 
drums. If this happens, the best thing to do is 
to jack the wheel up and squirt gasoline on the 
drum, slowly revolving it meanwhile. Manu¬ 
facturers usually put a plug in the differential 
case showing the proper height at which to keep 
the oil level. The gear box should be kept a 
little less than half full. If too much is put in. 
the oil will be thrown out of the shaft and 
bearing housings, but a little leakage does no 
harm as there is always dust present and the 
oil leaking will serve to fill the crevices and 
make the case dust-tight. In regard to the 
wheels, universal joints, clutch, and many lit¬ 
tle places about the car, all need attention oc¬ 
casionally as almost any motor car driver 
knows. 

The wheels should be cleaned and packed 
with grease once or twice a season, universal 
joints at intervals necessarily shorter. Latest 
designs provide for their lubrication through 
the shaft from the gear box. Earlier types are 
best packed in grease and enclosed in a leather 
boot. On many shaft-driven cars, where the 
shaft runs through a sleeve, daily attention 
should be given. The lack of a few T .drops of 
oil may rob the car of 50 per cent of its power. 
Multiple disc clutches use oil, or an oil and ker¬ 
osene mixture, and the tendency seems to be 


The Automobile Handbook 


467 


for the oil to gum. Their action when slipping 
or dragging is sufficient indication as to when 
they are in need of attention. Leather-faced 
clutches will work much better when cleaned 
with kerosene and given a dose of neatsfoot or 
castor oil. The oil should be spread over the 
surface of the leather by using a long knife 
blade, or by running the motor for a few mo¬ 
ments with the clutch released. When treating 
the clutch leather this 1 way it is better to let 
it stand over night if possible, and with the 
emergency brake lever, or a block of wood 
against the pedal hold the clutch disengaged. 
A hand oil can with a long spout is almost in¬ 
dispensable, and the starting crank, the steer¬ 
ing pivots and connections, and the spark and 
throttle connections, gear control and emer¬ 
gency brake levers, clutch and brake pedals, 
shafts and connections and the fan bearings 
will all work much quieter and sweeter for a 
few drops of oil regularly. It is the practice of 
drivers to fill the oil can from the cylinder oil 
supply and this practice is to be commended, 
as many lower grade oils contain acids enough 
to etch steel. 

Magnetos. The basic principles upon which 
the magneto operates have already been ex¬ 
plained under the head of Generators, and need 
not be again alluded to. Several of the leading 
types of magnetos in use on modern automo¬ 
biles will be described, and their action illustra¬ 
ted and explained. 


468 


The Automobile Handbook 


Wiring Diagrams. In Fig. 206 is shown a 
wiring diagram of a high-tension magneto for 
a four-cylinder motor. In a true high-tension 
magneto the current is transformed from the 
comparatively low-tension current delivered hy 
the magneto armature, to a high-tension current 
of sufficient pressure to overcome the resistance 
of the air gap between the electrodes of the 
spark plug, by means of a secondary winding 



on the armature itself. Thus the whole appar¬ 
atus is self-contained, and requires no separate 
transformer coil, which greatly simplifies the 
wiring. There are only five wires leading from 
a high-tension magneto for a four-cylinder mo¬ 
tor; four of these lead to the spark plugs, and 
one to the ground. The switch is placed on the 
ground wire, and when closed, short-circuits the 
primary current of the magneto and prevents 
the induction of a secondary current, therebv 



























The Automobile Handbook 


469 


stopping tlie sparking at the plugs. In Fig. 207 
a low-tension system is shown. This is more 
simple than the wiring of a high-tension sys¬ 
tem, only two wires leading from the magneto 
—the one carrying the current to the insulated 
terminals of the make and break, or magnetic 
plugs; and the other being a ground wire, 
which unlike that of the high-tension system 
must be opened to stop the motor. A wiring 



diagram for a two-cylinder motor with a single 
coil and distributer is shown in Fig. 208. 

Magneto—Bosch Low-Tension. The Bosch 
electro-magnetically operated spark plug is il¬ 
lustrated in Fig. 209 and Fig. 210. It consists 
of a coil A, one end of the winding of which 
connects with a terminal B and the other with 
the plug casing C which threads into the cylin¬ 
der of the motor. A spark is produced when 
a separation takes place between the moving 




























470 


The Automobile Handbook 


contact D and the stationary contact E on the 
end of this plug, which separation is accom¬ 
plished in the following manner: Within the 
plug is a metal core F and a swinging lever G, 
which lever pivots on the knifed edge projec¬ 
tion II which is a part of the core F. K shows 
a portion of a hair-pin spring, the end L of 
which rests in a recess with the lever G, the or¬ 
dinary tension of the spring tending to hold the 
lower end of the lever G carrying the contact 



1) against the stationary contact piece E. The 
operation of the plug is briefly as follows: 
When the distributer forms a contact for giving 
a spark to any cylinder, the circuit through the 
plug is through the contact B and the coil A, 
thence through the plug casing C and back to 
the motor. The completion of the circuit ener¬ 
gizes the core F which tends to pull the upper 
end M of the lever G towards the right, but it 
is protected from contact into the core by the 
























The Automobile Handbook 


471 


noil-magnetic brass plug N. The pulling of the 
upper end of the lever G to the right carries the 
lower end to the left, separating it from the 
stationary contact E, thereby breaking the cir- 



Fig. 209 

Boscli Electro-Magnetic Plug 


cuit. Immediately the circuit is broken the 
coil A surrenders its electro-magnetic power, 
the core F is degenerized and the end of the 
hair-pin spring L forces the lower end of the 

























































472 


The Automobile Handbook 


lever G to the right, as the spring L exerts its 
pressure beneath the fulcrum II and which 
brings the contacts D and E together. At the 



Fig. 210 

Assembly Bosch Plugf 

«/ o 


bottom of the contact piece there is an insu¬ 
lated fixed stem which is magnetically divided 
in about the middle by means of a brass part, 
so that when the current passes through the 




























































The Automobile Handbook 


473 


coil A only the portion of the stem above the 
brass part can be magnetized, and, as a result 
of this magnetization the upper end M of the 
interrupter lever G, which directly faces the 
magnetized part, is attracted, the lower end D 



Fig. 211 
Bosch Magneto 

simultaneously breaking contact with the con¬ 
tact piece E, thus interrupting the current and 
producing a spark. In the normal position of 
the interrupter lever G. the lower end presses 
against the contact piece E. being kept in that 
position by the horseshoe-shaped spring K, 



474 


The Automobile Handbook 


which passes right over the top of the stem and 
lies in slots in the sides thereof. 

The top of the coil is fitted with a contact 
screw to which the current from the magneto 
is led. This magneto, Fig. 211, generates an 
ordinary low-tension current and is provided 
with a low-tension distributer distributing the 
current to the individual plugs, according to 
the number of cylinders, so that only one low- 
tension wire for each plug is employed. The 
distributer disc is shown separately in Fig. 212, 
as well as the interrupter, which latter is pro¬ 
vided for the purpose of timing the ignition. 

Regarding the magneto of Fig. 211 as used 
for the plug, Figs. 209 and 210, it is of interest 
to know that the magneto is made for three, 
four and six cylinder motors, the distributers 
having corresponding numbers of pick-up car¬ 
bon brushes and terminals. Their armatures 
are driven at three-quarters, equal, and one and 
a half turns of the crankshaft respectively; each 
is made in two patterns, according to the di¬ 
rection of rotation, which should be stated 
when ordering. The range of timing is about 
60 degrees, 50 degrees, and 34 degrees, rela¬ 
tively to the crankshafts of the three types of 
engine. The lever has a certain amount of 
side play, so that if two of the contact sur¬ 
faces at D become fouled, a slight scraping ac¬ 
tion is set up between the other two, and a 
good conductor is assured. Xot only must the 
magnetic plugs be set vertically, but they must 


The Automobile Handbook 


475 


be arranged where their metallic exteriors are 
clear of other parts, and also where they can 
be kept cool. 

Fig. 213 is a diagram of the electrical ar¬ 
rangements, which will be seen to be similar to 
those of the Bosch high-tension magneto. A 
portion of the wiring of the armature is short- 



circuited by the platinum points of the inter¬ 
rupter, and when the circuit is interrupted, the 
resulting armature reaction has the effect of 
raising the voltage of the armature sufficiently 
to operate the magneto plugs. The rotating 
distributer bar is adjusted in such a manner 
that it is always in connection with one of the 





476 


The Automobile Handbook 


spark plugs at the moment when the contact 
breaker of the magneto interrupts the circuit, 
so that the circuit to the plugs is closed and 
these are magnetized for operation. The spark 
is advanced or retarded by rotating the timing 



lever, in the same manner as with a high ten¬ 
sion magneto, and the timing corresponds to 
an angle of 50 degrees on the armature shaft. 
The magneto is switched off in the same manner 
as a high-tension magneto, by making a ground 















































































The Automobile Handbook 


477 


connection. This is done by small plug* switches 
with either a single plug, or a number of plugs 
corresponding to the number of cylinders. This 
makes it possible to switch each cylinder out 



separately for testing purposes, from the seat 
while the car is in motion. 

Magneto—Bosch High-Tension. The Bosch 
high-tension magneto, or generator differs from 
the standard rotary armature type in two re¬ 
spects only. First, the high-tension eonnec- 


478 


The Automobile Handbook 


tions are slightly altered, and, secondly, an ad¬ 
ditional contact breaker for the battery is pro¬ 
vided as shown in Fig. 214, so that the magneto 
will also serve as a timer for the battery, while 
"the one high tension distributer is used with 
both the magneto, and the battery current. All 
other details of the high-tension system are 
similar to those of the low. A special coil is 
provided for battery ignition, having a self- 
contained switch, and button for bringing a 



Fig. 215 

Bosch Armature 


magnetic vibrator into circuit when desired, for 
the purpose of starting the motor from the 
seat when there is any gas in the cylinder. The 
coil is of the general form of an IT armature, 
see Fig. 215, and not of the usual cylindrical 
form with concentric windings. It possesses 
the same amount of self-induction as the mag¬ 
neto armature, and while the engine is run¬ 
ning, the two systems are absolutely synchron¬ 
ized. and no difference is apparent in the speed 



The Automobile Handbook 


479 


of the engine, whether the magneto, or the bat¬ 
tery is used for furnishing the spark. 

The trembler is used only at the moment of 
starting. The button switch for bringing it 
into circuit is fitted in the lid of the case in- 
such a manner as to render it water proof. The 



Fig. 216 


connections are made by small segments in the 
bottom plate of the coil frame, the entire coil 
being moved toward the left, or the right to 
effect a change over. The switch handle pro¬ 
jects through a circular slct in the housing, and 
locks in three positions, designated respect- 


i 












/ 

480 The Automobile Handbook 

ively, “Magneto,” “off,” and “battery.” For 
inspection purposes, unscrew the switch handle, 
and remove the lid, when the coil may be taken 
out without disconnecting any wire. On some 
machines, particularly racing autos, a large 


Fig. 217 

Coupling Device for Bosch Magnetos 

timing range is required. This necessitates the 
shifting of the magneto armature with respect 
to the driving shaft, which can be done by 
means of the coupling shown in Figs. 216 and 
217. In Fig. 217 are shown two rotary sleeves, 
one fitting into the other, both being provided 






The Automobile Handbook 


481 


with helical slots running* in opposite direc¬ 
tions, so that by removing the collar that car¬ 
ries pins which extend into the slots, an angu¬ 
lar movement of these sleeves relative to each 
other up to 60 degrees is obtainable. 

Eismann Magneto. There are two types of 
the Eismann magneto. First, the .low tension 
magneto requiring a transformer to raise the 
voltage of the current; and second, the high 
tension magneto, which has a double winding 
on the armature and does not require a non- 
vibrator coil. 

The low tension magneto gives off from 20 
to 40 volts only. One end of the armature 
winding is grounded, the live end passing to 
the insulated contact of the interrupter, which 
is located at the end of the armature shaft. 
From this point the circuit continues to one 
terminal of the primary winding of the coil, 
the other terminal of which is grounded. The 
grounded part of the interrupter, a pivoted le¬ 
ver, is operated by a cam carried on the arma¬ 
ture shaft, and makes and breaks contact with 
the insulated part. Th$ earn is set in such re¬ 
lation to the armature that the breaking of the 
circuit by the interrupter coincides with the 
production of maximum current in the arma¬ 
ture winding. When the interrupter is making 
contact, the magneto current is offered two cir¬ 
cuits by which it may flow to ground, one 
being through the interrupter and the other 
through the primary winding of the coil. The 


482 


The Automobile Handbook 


resistance of the former being low, the current 
takes that path in preference to the other, 
which is of higher resistance. When the cur¬ 
rent reaches its maximum the cam breaks the 
interrupter circuit, and the only path by which 
the current can then flow to ground is that of¬ 
fered by the primary winding of the coil. This 
sudden and intense flow causes the core of the 
coil to throw out a powerful magnetic field, 



Fig. 218 

Eisemann High-Tension Magneto 


which induces a current in the secondary wind¬ 
ing of from 20,000 to 40,000 volts. This current 
is passed to the proper spark plug through the 
medium of a distributer located op the magneto 
and driven by the armature shaft. A condenser 
is connected across the interrupter contacts to 
reduce the sparking as the circuit is broken, 
and to effect a more abrupt change in the mag¬ 
netic field of the coil. 












































































The Automobile Handbook 


483 


1 lie latest Eisemann magneto is of the high- 
tension type, as shown in Fig. 218, in which A 
is the cam nut; B, steel contact for high-ten¬ 
sion distributer; C, platinum contact for make- 
and-break lever; D, high-tension distributer 



Fig. 219 

General Wiring Diagram for Eisemann Magneto 

cover; E, nut for adjustable contact screw; 
F, spring for make-and-break lever; G, carbon 
contact for high-tension distributer; H, make- 
and-break lever; I, low-tension carbon brush; 
K, adjustable platinum contact screw; L, grease 
box for large toothed wheel; M, nut; N, cam: 





























































484 


The Automobile Handbook 


O, cable joints; P, distributer plate; Q, metal 
contact; S, screw for spring for make-and- 
break lever; V, high-tension distributer. 

Magnetos are made to turn in either direc¬ 
tion, but the magneto once finished turns in one 
direction only, and this direction is indicated 
by an arrow placed on the gear wheel case. 



Steering wheel 
Interrupter 


Fig. 220 

The spark occurs in one of the cylinders at 
the moment that the contact points are sepa¬ 
rated by the cam. The advance mechanism is 
arranged in three different ways : (1) by means 
of a lever working the make-and-break mechan¬ 
ism (quadrant advance) ; (2) by means of a 
piston sliding longitudinally, and fitted to the 
end of the driving axle (piston advance) ; (3) 
by rocking the magnets bodily around the ar- 



































The Automobile Handbook 


485 


mature (pivoting advance). In all cases a dis¬ 
placement of 45 degrees can be obtained. In 
magnetos with quadrant advance the driving 
spindle is fixed by means of a pin and nut. 

This type of magneto is consequently shorter 
than the one with piston advance. In the lat¬ 
ter ease the driving pinion is fixed on a hollow 
spindle. 

Timing the Eismann Magneto. When tim¬ 
ing a magneto with quadrant advance, push 
lever as far as possible in the direction of rota¬ 
tion (looking from the driving end). In this 
position the time of ignition is “fully retarded.” 
Turn motor by hand until the piston of the en¬ 
gine, corresponding with the metallic contact 
piece on which presses the distributer finger, 
has gone a very small distance beyond the dead 
point. Turn armature of magneto until the line 
which is marked on cam stands right opposite 
the pin screwed into bearing plate (moment at 
which spark takes place). Fix driving pinion 
in this position. By gradually displacing the 
lever it is possible to give the motor the re¬ 
quired spark advance. 

When timing a magneto with piston advance 
the timing of the ignition is the same, whether 
the magneto is turning clockwise or otherwise. 
Pull out the piston (retard), and proceed ex¬ 
actly as above described. By gradually push¬ 
ing the lever into the hollow spindle the re¬ 
quired advance is obtained. 

When timing a magneto with pivoting ad- 


The Automobile Handbook 


486 

vance, move the magnets as far as possible in 
the direction of rotation (retard), and proceed 
again exactly as with the quadrant advance. 
By gradually altering position of the magnets 
the required advance is obtained. 

To start engine it is sufficient to give a sud¬ 
den jerk to the starting handle at the moment a 



Primary distributor half 
speed of crank shaft 


Fig. 221 

Wiring Diagram for Eisemann Dual Ignition System 

spark is to take place in one of the cylinders. 
If the motor does not start off at once, this may 
I 3 e caused. a, tltr setting not being done in 
a proper way; b, by the points of the plugs be¬ 
ing too much apart (about 0.5 millimeters) ; c, 
by the cables being faulty or the connections be¬ 
ing badly made. Very often the carburation is 


































The Automobile Handbook 


487 


faulty. In any case care should be taken, when 
stopping the motor, to suspend the action of 
the magneto, and to cut off the supply of gaso¬ 
line when the motor has ceased running. In 
this way the cylinders are prevented from get¬ 
ting filled with air. If the cylinders contain 
gasoline, the starting of the motor is always 
easy. If, on the contrary, the supply of gaso¬ 
line is cut off while the motor is running, the 



Eisemann-Panliard Dual Ignition System 


cylinders get filled with air, and on restarting 

1/ c 

it has to be driven out and replaced by gasoline. 

Clean frequently with gasoline: a, the carbon 
brush at the end of the armature spindle; b, 
the platinum contacts; c, the metallic contact 
pieces in distributer disc. 

If the platinum contacts are worn off. be care¬ 
ful that in setting or resetting them the con¬ 
tacts are not separated from each other more 
than one one-hundredth of an inch. In order 


























488 


The Automobile Handbook 


/ 

to facilitate the setting, two equal spanners 
must be used. Do the setting in the following 
way: 

Loosen with one of the spanners the lower 
brass nut of the platinum contact holder, and 
then, by turning the upper brass nut, screw the 
platinum contacts upwards or downwards. If 
the adjustment is properly done, the contacts 
should be separated from each other, not more 
than one-quarter millimeter at the moment 
when the contact lever is raised by the cam. 
Then hold the upper brass nut with one of the 
spanners and fasten the lower brass nut with 
the other spanner. 

If, for any reason, the magneto has been taken 
to pieces, be careful that when remounting same 
the numbers stamped on the gear whepls are 
exactly opposite each other. In case of any 
irregularity of the sparking, examine the mag¬ 
neto and coil in the following way: a, plugs. 
In order to find out whether the fault lies with 
the plugs, screw on new plugs and test the 
motor with them, b, cables. Examine whether 
all the cables are connected according to the 
wiring diagram. Make sure that they are not 
damaged, and that their ends do not touch each 
other or some metallic part of the magneto, 
whereby the current would be short-circuited. 

On the type shown in Fig. 218, such as is used 
on the Packard 1909 car. the carbon brush at 
the end of the armature spindle inside the 
make and break cover, the platinum contacts 


The Automobile Handbook 


489 


C 1 and K, also the metal contact Q, and the me¬ 
tallic contact pieces in distributer disc should 
be frecpiently cleaned with gasoline. When 
setting platinum contacts C and K, or contact 
lever II, the circuit breaker should be taken 
off. Put through the hole in the plate, the 



Fig. 223 

Magneto Used on the Ford Cars 


metal adjuster that is supplied with the mag¬ 
neto, and which has exactly the same diameter 
as the cam on the armature spindle. Then 
screw up or down the lower platinum contact 
K until a bit of paper can be slipped between 
the contact without getting jammed. In this 






















































































































The Automobile Handbook 


490 

position the contact screw is held by means of 
a screw driver, while nut E is fastened. 

Ford Magneto. The Ford magneto, Fig. 
223, is of a peculiar design, it being constructed 
as an integral part of the flywheel, in which A 
is the support for the magneto coils; BBB, mag¬ 
neto coils; CC, permanent horseshoe magnets; 
DO, the flywheel; E, planetary pinions; F, low 
speed break band; G, reverse brake band; H, 
disc-clutch for high speed; I, transmission 



Details of Ford Magneto 


brake; J, clutch rocker shaft, and Iv, high speed 
clutch spring. The permanent magnets, which 
are U-shaped, nre bolted to the forward face of 
the flywheel, as shown in Fig. 224. Close in front 
of their outer ends is a series of insulated coils 
mounted in a circle of practically full flywheel 
diameter, with their axes parallel with that of 
the crankshaft. They are supported upon a 
stationary spider, as shown in Fig. 225. As the 
flywheel revolves, this magnet and coil com¬ 
bination, which is similar to that used on some 








The Automobile Handbook 


491 


types of alternating current generators, pro¬ 
duces a current which is used through a four- 
unit current timer to cause the ignition spark. 
The magneto is of the inductor type, the arma¬ 
ture coils being stationary, and the field mag- 
nets moved past them. Sixteen separate field 
magnets are used, made of vanadium-tungsten 
steel. They are substantially horseshoe shape, 
being secured to the side of the flywheel as illus¬ 
trated in Fig. 225. They are held in place by 
screws at their middle, and by clamps near their 
poles, all screws used for fastening them being 
securely locked in place by Wire locks. 

The magnets are so arranged that, like poles, 
they are adjacent to each other, forming a six¬ 
teen pole field magnet crown. Instead of being 
placed close against the flywheel, these mag¬ 
nets are clamped against a ring of non-magnetic 
material (brass for instance), in order to re¬ 
duce leakage of magnetism through the fly¬ 
wheel rim. At their middle these magnets are 
fastened directly to the flywheel, as at this point 
they are neutral, and there can be no leakage. 
A series of sixteen armature coils is carried on 
a coil supporting ring slightly in front of the 
flywheel, as shown in Fig. 224. These coils are 
wound with heavily insulated magnet wire, and 
are so grouped around the supporting ring that 
the winding of adjacent coils is in different di¬ 
rections, one being wound clockwise, and the 
next one counter clockwise. The coils are con¬ 
nected in series, the terminals being brought 


492 


The Automobile Handbook 


out near the top of the casing*. As the poles 
of the magnets are located opposite and very 
close to the coils, the magnetic circuits are com¬ 
pleted by the cores of these coils and the coil 
support. There are evidently sixteen electrical 
impulses produced during the revolution of the 
crankshaft and flywheel, although only two im¬ 
pulses are required for the ignition of the mo¬ 
tor, one per stroke. However, as the armature 
circuit is closed only when a spark is wanted, 



Fig. 226 
Herz Magnets 


a current only flows at that period, and there 
is no loss from the other impulses. 

IIerz High Tension Magneto. This mag¬ 
neto differs from the regular conventional type 
in that it is cylindrical in shape, due to the em¬ 
ployment of ring-shaped field magnets A—Fig. 
226—instead of the horseshoe type generally 
adopted. The six Herz magnets are in reality 
as many flat steel rings clamped together with 
a polar space, or armature tunnel, C, cut iq 









The Automobile Handbook 


493 


them. The ring surfaces are ground with the 
utmost accuracy in order to obtain the best 
magnetic effect when they are all clamped to¬ 
gether. These magnets are mounted on an 
aluminum base S. A second unconventional- 



ity is that the usual independent, soft-metal 
pole pieces, which bolt to the ends of the horse¬ 
shoe magnets in the conventional magneto, are 
dispensed with entirely. In the Herz system 
the space C, which accommodates the armature, 















494 


The Automobile Handbook 


is bored out from the magnets A, and in this 
manner sharp angles in the magnet system, 
which invariably result in a leakage of lines of 
force in the magneto, are avoided. The arma¬ 
ture D, Fig. 227, is of shuttle shape, accommo¬ 
dating the low, and high-tension windings E 
within the frame portion of it. So careful has 
the construction of this armature been superin¬ 
tended that there is but 1-10-millimeter air 
space between it and the curved portions of the 
magnets A. The armature revolves on ball¬ 
bearings, mounted in special cages, and is fitted 
with lubricating means sufficient for many 
months’ use. The armature windings consist 
of a primary winding, in which is generated the 

low-tension current and also a secondarv wind- 

«/ 

ing in which is generated the induced, or high- 
tension circuit. At one end of the armature, 
and encased in a brass box, is the condenser, F, 
Fig. 227. 

The make-and-break devices for interrupting 
the primary circuit are illustrated in Fig. 227, 
the entire device being a detachable unit, which 
secures to the armature shaft by a key-way and 
feather. This make-and-break mechanism con¬ 
tacts with one end of the primary winding of 
the armature through a small carbon brush, fit¬ 
ted into the contact disk, which presses against 
a ring alongside of the ball race on the arma¬ 
ture. The contact device consists of three 
parts: First, a curved spring G, having a plat¬ 
inum flat contact on one end; a steel block H 


The Automobile Handbook 


495 


carrying an adjustable platinum contact, and 
a small, hard-fiber roller K carried on a pin. 
This roller is set so that if it is given a slight 
push at the edge it tends to move up the in¬ 
cline plane formed by the steel piece H, and in 
doing so pushes against the end of the spring G 
and separates the platinum contacts L. This 



contact-maker revolves bodily with the arma¬ 
ture, and in its rotation the fiber roller K strikes 
upon two steel projections M—Fig. 228—held 
in the case, thus breaking the circuit at the 
points of maximum induction twice in each rev¬ 
olution, at which time the induced current is 
set up in the secondary winding of the magneto. 

It is scarcely necessary to comment here that 











496 


The Automobile Handbook 


the primary and secondary windings are thor¬ 
oughly insulated from each other, and that, 
with the making and breaking of the primary 
current an induced current is set up in the sec¬ 
ondary winding, which because of the many 
turns of wire in this winding, is of a particu¬ 
larly high voltage. For cutting off the spark 
when desired a terminal is provided on the con¬ 
tact-maker case, which gives a connection by 
means of a spring pressing on the head of a 



Fig. 220 

High-Tension End 


steel screw in connection with the insulated 
end of the primary winding, which thus can 
be short-circuited at will. In advancing or 
retarding the spark, connections are made with 
the ball-ending N, Fig. 228, the contact-maker 
. having a 30-degree movement for this purpose. 
The high-tension end of the armature has 
mounted upon it a deeply recessed insulating 
collar, with a metallic sector within it. Upon 
this sector are small carbon brushes for draw- 











The Automobile Handbook 


497 


ing off the high-tension current. In Fig. 229 
appears a magneto suitable for a two-cyl¬ 
inder engine with its high-tension terminals 
R located at 90 degrees to each other. To ob¬ 
tain the two sparks the high-tension contact 
/ 

piece, or sector is fitted with an insulating col¬ 
lar, which does not go quite half way round, 
and thus makes alternate contact with the two 
carbon brushes R, sending the spark to the re¬ 
spective cylinder. In four-cylinders a distrib¬ 
uter is combined. The safety spark gap is 



Fig. 230 

Inductor Magneto Shaft 


located between the high-voltage sector and the 
armature, and if the spark exceeds % inch it 
bridges the insulating collar to the armature. 

High Tension Inductor Magneto. This 
type of magneto, now so extensively used for 
ignition purposes, is a comparatively recent 
product, the result of many years of experiment 
and development. The principles of its action 
are as follows: By revolving a solid steel shaft 
on which are two drop-forged steel magnet in¬ 
ductor wings, Fig. 230, the magnetic field is 


498 


The Automobile Handbook 


reversed twice during' each revolution, and 
creates two electrical current waves, or im¬ 
pulses per revolution. The direction of flow 
of the magnetic current is changed at each im¬ 
pulse, thereby generating an alternating cur¬ 
rent. A circular shaped stationary winding of 
magnet wire is imbedded between the poles of 



Fig. 2:> 1 

Distributor for Inductor Type 


the magnets and around the inductor shaft, 
and a strong current is generated in it and car¬ 
ried directly through the circuit breaking de¬ 
vice by means of heavy lead wires, thus dis¬ 
pensing with the use of carbon brushes and col¬ 
lector rings. 

There are no revolving windings nor mov¬ 
ing contacts, and consequently many sources of 






The Automobile Handbook 


499 



trouble are eliminated. The current is carried 
to the transformer coil located on the dash¬ 
board, where it is stepped up to the high volt¬ 
age necessary for creating the hot jump-spark. 

From the transformer the current is con¬ 
ducted back to a hard rubber distributer, see 


Fig. 232 

o _ 

Longitudinal Section Through Inductor Type of Magneto 

Fig. 231. on the face of the magneto, and from 
thence to the spark plugs. The distributer 
shaft, located immediately above the inductor, 
revolves a metallic segment past the terminals 
of the wires leading to the spark plugs. The 
high tension current is carried to this segment, 
and transmitted to the spark plug. A magneto 







500 


The Automobile Handbook 


of this type, and gear driven, gives what may 
properly be called perfect timing. A hot spark 
is delivered in the cylinder under compression 
at the exact instant desired. 

The device is also reliable for starting the 
motor from the seat without cranking, for the 
reason that the motor always stops with the 
magneto in such a position that the first spark 
will occur in the cylinder under compression, 
and where batteries are used a push button is 
provided, which by merely touching will cre¬ 
ate the spark where needed. Fig. 232 shows a 
sectional view of the magneto. 

llow to Remove and Replace a Magneto. 
When about to replace or remove a magneto it 
is well to see that all separable parts are prop¬ 
erly marked, and if not, mark them. This may 
be done with a center punch, cold chisel, letters 
or numerals. In Fig. 233 is shown the guide 
marks generally used in connection with a high- 
tension magneto of a four-cylinder motor. The 
center punch marks C, on the Oldham coupling 
such as is usually employed on the magneto 
shaft between the magneto and its driving gear, 
serve as a guide in replacing the magneto. All 
that is necessary in replacing a high-tension 
magneto so marked on a four-cylinder, four¬ 
cycle motor is to see that the marks are directly 
opposite each other; but in two or six-cylinder 
motors, where the crankshaft and the armature 
of the magneto do not run at the same speed, 
care must be taken either not to move the 


The Automobile Handbook 


501 


crankshaft while the magneto is off or to check 
up the timing before it is replaced. In the 
same illustration is shown the method of mark¬ 
ing the timing gears. These marks are made 

• 

with a ^old chisel and are generally present in 
up-to-date construction. When a new gear is 
fitted to a magneto, or to the crank, or cam¬ 
shafts for that'matter, it should be marked in 
the same place relative to the key way as the old 



gear, and both marks A and B should line up 
properly when the gears are in mesh. 

Magnetic Clutch. The elimination of the 
clutch has long been a dream of automobile in¬ 
ventors. Many attempts also have been made 
to simplify, or dispense with the differential 
gear, another source of trouble and expense. 
Figs. 234, 235, 236 and 237 show views of a 
magnetic clutch and transmission, the efficiency 
and reliability of which is yet in the balance. 
Referring to Figs. 234 and 235 it will be noted 











502 


The Automobile Handbook 


that the rear axle is made in one piece, so pro¬ 
portioned as to have the greatest section at the 
point of maximum bending moment, which 
point is the center, thus giving great strength 
to the whole rear construction. On the outer 
ends of the rear axle are keyed a pair of mag¬ 
netic clutches, one at each end. Except for 
the diameter, which is slightly greater, these 



Fig. 234 

The One-Piece Rear Axle Looms Up Large 

ure the same as the clutches used to operate 
the transmission gears. The action is the same 
also. 

AVhen current is turned into the magnet E, 
contained within a recess in plate D, the corre¬ 
sponding plate P, incorporated in the rear wheel, 
is attracted and, as long as the current passes 
and energizes the magnet, the wheel is driven 
by the rotating rear axle. As soon as current 



















































































The Automobile Handbook 5(j; : 

is cut off the wheel is freed, and is no longer 
dri\ en by the motor. This is the action which 
displaces the differential. The steering gear 
turns free up to a certain angle, at which it 
automatically cuts off the current to the inner 
wheel, which is thus disengaged, while the outer 


Fig. 235 

View of Rear Construction, with Wheel Removed 

wheel continues to drive the car, the result be¬ 
ing a perfect differential action, all being ac¬ 
complished automatically by the simple move¬ 
ment of the steering gear, no manual work by 
the driver being necessary. 

The brake drums, wheels and other parts are 
standard as shown in Fig. 235, in which M is 









504 


The Automobile Handbook 


the magnetic clutch, and F 1 and F 2 are the two 
halves of the hub brakes. 

The transmission is of the individual clutch 
type, the clutches consisting of electro mag¬ 
nets. 

Fig. 236 shows the arrangement, the jack¬ 
shaft being above the main shaft. Upon the 
latter the gears are placed which are clutched 
up to the shaft to obtain the different speeds. 
These are three in number with direct drive on 



Fig. 236 

Transmission Parts, Showing Clutches in Place 

the high. To engage any gear, a current is 
impressed on the windings of the magnet, which 
is keyed to the shaft. This attracts the plate car¬ 
rying the gear, and the desired speed is thereby 
obtained. There are four of these electro mag¬ 
nets, and four of the plates, that for the high 
speed being made integral with the gear itself. 
Fig. 237 shows the plates and other parts com¬ 
prising the whole of the two clutches. M 1 is a 
full view of the magnetic plate, and shows the 








The Automobile Handbook 


505 


keyways for securing it to the shaft. B is the 
magnet complete with a wire leading to the 
rings. M 2 shows the magnet set into place. 
These represent at the same time the gears 
themselves and their method of operation and, 
with the case, and bearings complete the trans¬ 
mission. Two sources of electric current are 
required. In addition to the ordinary ignition 
equipment, there is another magneto for sup- 



Fig. 237 ' 

How the Magnetic Clutches Look When Dissembled 

i 

plying current to the magnets. This is located 
upon an extension of the lower half of the gear 
box, extending from the side of the box to the 
main frame on the right hand side, forming a 
wide shelf. This magneto is enclosed in a 
water-tight ease, and is belt driven from the 
cardan shaft. It is constructed with special 
windings to produce a current of perfect con¬ 
stancy but limited amperage. At very high 
speeds the voltage increases slightly. 






506 


The Automobile Handbook 


The following advantages are claimed for 
this specially wound magneto over accumula¬ 
tors for this particular work: (1) less weight: 
(2) smaller loss of voltage; (3) less danger of 
short-circuits; (4) increased reliability. 

Manifolds—Correct Designs for. Since the 
gasoline enters the intake in the liquid state, 
and since there is not sufficient heat available 
in the air that enters to assure vaporization, 
the greater the length of the manifold within 
certain limits, the greater will be the chance of 
vaporizing the gasoline especially after the mo¬ 
tor is started, because some heat will pass 
through the walls of the manifold and be thus 
communicated to the entrained liquid in the 
mixture while in the manifold. The deliverv 

i/ 

of an equal weight of the mixture to each of the 
cylinders is another important point for con¬ 
sideration, and depends largely upon the design 
of the manifold, although condensation and the 
mechanical separation of the non-vaporized gas¬ 
oline are two factors that tend also to prevent 
a uniform distribution of the mixture to the 
cylinders of the motor. 

Besides length, area must be considered. If 
in a single-cylinder motor, the area of the mani¬ 
fold is one-quarter the area of the piston, and 
if the length is four times the stroke of the en¬ 
gine, it is evident that the mixture will be al¬ 
lowed to rest in the manifold during the period 
of one complete cycle in a four-cycle motor. 

If the motor develops maximum power at 


The Automobile Handbook 


507 


1,600 R. P. M. the mixture will nominally rest 
in the manifold for a period of time equal to, 

S 1600 

t=-=-=6.6 

60Xc 60X4 

in which 

t=ratio of time mixture will lie in manifold 
of a single cylinder motor. 

S=angular velocity of crank shaft in R. P. M. 
C=eyelic period of motor. 



Fig. 238 


In a single cylinder motor the relation of the 
volume of the intake in relation to piston dis¬ 
placement becomes an easy problem, but when 
the number of cylinders is increased the prob¬ 
lem becomes more complex. 

The relation of manifold area to piston dis¬ 
placement should be maintained, otherwise the 
torque of the motor may fall off as the speed 
increases. Fig. 238 shows a correctly designed 
manifold for a two-cylinder opposed motor and 
it will be noticed that while the intake is long 
























508 


The Automobile Handbook 


and slender, the connections to the cylinders 
are made in such a way as to cause an equal 
distribution of the mixture. 

Fig-. 239 shows a manifold for a four-cylinder 
motor, designed in such a way as to distribute 
the mixture to the respective cylinders with 
the least change in direction of How and at the 
same time have all the cylinders at the same 
distance from the carbureter, as nearly as pos¬ 



sible. In the case of siamesed cylinders the 
same results may be arrived at by using a mani¬ 
fold similar to the one shown in Fig. 240, in 
which the carbureter is well below the valves 
of the motor, and the Y with long, easy bends 
branches from the riser at a low point. 

Another design is shown in Fig. 241, involv¬ 
ing a Y-shaped manifold with a casting of a 
box-like character, possessing no dividing Avails 















The Automobile Handbook 509 

excepting- those which separate the mixture 
from the exhaust gases that enter a cored por¬ 
tion of the casting, near the cylinders, high up, 
for the purpose of aiding in the process of evap¬ 
oration. In view of the large amount of gas 
that can be stored in the space afforded it is 
likely that benefits follow its use, although, in 
the absence of exhaust heat, the space might 
be regarded as excessive. 



Fig. 242 shows a manifold in which the en¬ 
largement is above the riser, although a part of 
it. This manifold is used on four-cylinder mo¬ 
tors, but does not afford as large an area for 
the transfer of heat, which is really not a ne¬ 
cessity, provided the carbureter is so designed 
that it will properly vaporize the mixture, and 
free it from entrained liquid. 

The manifold shown in Fig. 243 for a four- 
cylinder motor is but a development of the Y 















510 


The Automobile Handbook 


shown in Fig. 240, possessing the advantage of 
no change in direction of flow of the mixture 
to the different cylinders. Another commend¬ 
able feature in this type of manifold is its neat 
appearance, but when this plan is applied to a 
six-cylinder engine, as shown in Fig 244. certain 
complications arise, not the least of which is 
that the gas is compelled to go in a reverse di¬ 
rection in order to get to cylinders 3 and 4. 
Also the distances to cylinders 1 and 6 are con¬ 



siderably increased. These, with other faults 
in the design will no doubt tend to lessen its 
efficiency when applied to a six-cylinder unit. 

Fig. 245 presents a view of a manifold for a 
six-cylinder engine, in which an attempt is made 
to equalize the pressures of the gas streams 
in their passage to the cylinders. Although the 
flow is not in one common direction, still the 
distribution is much better than that attained 
in Fig. 244, and the area of surface afforded 









The Automobile Handbook 


511 


for the transfer of heat is also much larger. 
The manifold shown in Fig. 246 is designed 
with a view to the balancing of the forces due 
to so-called “inertia” of the gas, and it will be 



noticed that the branches leading to the re¬ 
spective cylinders are connected in such a way 
as to offer equal resistance in all directions to 
the passage of the gases. This manifold, it is 
said, gives good service in actual practice. 



Marking Car Parts. Taking mechanisms apart 
for repairs is very often one of the most trouble¬ 
some jobs at which a repairman can be pul. 
Between corrosion, dirt, and distortion, and 


















































512 


The Automobile Handbook 


perhaps fractures, it generally is the most dis¬ 
agreeable work of the shop. Often, too, the 
mechanism to be taken apart and repaired is 
one with which the repairman has no acqaint- 
ance; hence, he must feel his way, so to speak, 
or after it is taken apart he may find that put- 

i 

ting it together again is like solving an intri¬ 
cate puzzle. Before commencing to take any 
mechanism apart it should be thoroughly looked 
over in order to gain a clear idea of the general 



Fig. 244 


arrangement and location of parts. In most 
cases it will be necessary to mark similar parts 
by stamping, or with a center punch. It is cus¬ 
tomary among most manufacturers to stamp 
with letters or figures all adjoining parts which 
are individually fitted, such as connecting-rods, 
pistons, brasses and their blocks and caps, 
valves, push-rods, guides, gears, etc. Neverthe¬ 
less, care should be taken to see that all parts are 


















The Automobile Handbook 


513 


properly marked, and to mark those which are 
not. A large number of similar parts can be 
marked with center-pops, not only by increas¬ 
ing the number of pops, but also by arranging 
them in devices, as shown in Fig. 247. The 
marks should not be put on working, or ma¬ 
chined occlusal surfaces, but upon places where 
there is no direct contact. 

Motors—Two and Three Port. In the two- 
port motor, as illustrated in Fig. 248, the func¬ 
tions are as follows: 



Fig. 245 


The first stroke of the piston produces a vac¬ 
uum in the crankcase and the mixture rushes 
in (as a consequence) through the check valve 
in the motor case. The second stroke com¬ 
presses the mixture, and when the communicat¬ 
ing port is uncovered the mixture surges into 
the cylinder. The next (third) stroke com¬ 
presses the mixture entrapped in the cylinder, 
since the ports are then covered by the piston, 
and at the proper instant the mixture is ignited. 

From this point on it is a normal repetition 
of functions, and once the motor gets under 
way it two cycles. The three-port motor, Fig. 
249, differs in that the mixture is taken in 

















514 


The Automobile Handbook 


through a third port uncovered by the piston, 
instead of through a check valve in the case, 
and the details in practice change accordingly. 

Needle Valve. Valves with cone-points, and 
having a fine thread on the stem are known as 
needle-valves and are used for the regulation of 



the supply of gasoline to the carbureter or 
mixing valve of a motor. 

Non-Freezing Mixtures for Radiators. In 
cold weather, the circulating water, the oil, 
and the carbureter require special attention. 
If the car is to be run regularly during 


£ •• •• •• •• ••• •••• • • • •••• iy « <» 

Fig. 247 

Marking Designs 

the winter, it is advisable to use a non- 
freezing mixture in the water-jacket. If the 
car is not to be used regularly, it may not 
be necessary to employ such a mixture, but in 
that case great care is necessary to prevent the 
water from freezing unexpectedly. If the car 






























The Automobile Handbook 


515 


is kept in a barn, the water should be drawn 
off completely after the car has been used, and 
the drainage cock should be so located and the 
piping so arranged that there are no water 
pockets in which the water may freeze and ob¬ 



struct the circulation. If the water freezes in 
the pump, the latter is likely to be broken when 
the car is started the next morning. If water 
freezes in the water-jackets, it will burst the 
jackets unless they are made of copper. When 
the car is left standing for an hour or so, cloths 




















































516 


The Automobile Handbook 


or lap robes may be thrown over the radiator 
to check the cooling; this is cheaper and safer 
than leaving the motor running. 

The two substances most used to prevent 
freezing are glycerine and calcium chloride. A 
30-per-cent solution of glycerine in water 
freezes at 21° F.; and a solution of one part of 
glycerine to two parts of water is safe from 
freezing at 10° or 15° F.; 40-per-cent solution 
freezes at zero. A small amount of slaked lime 
should be added to neutralize any acidity in the 
solution. Glycerine has the objection that it 
destroys rubber, and the solution fouls rather 
quickly. 

A cheaper mixture, and one preferable where 
the temperatures encountered are likely to be 
below 15° or 20° F., is a solution of calcium 
chloride. This must be carefully distinguished 
from chloride of lime (bleaching powder), 
which is injurious to metal surfaces. Calcium 
chloride costs about 8 cents a pound in bulk, 
and does not materially affect metals except 
zinc. A saturated solution is first made by add¬ 
ing about 15 pounds of the chloride to 1 gallon 
of water, making a total of about 2 gallons. 
Some undissolved crystals should remain at 
the bottom as evidence that the solution is sat¬ 
urated. To this solution is added from 2 to 3 
gallons of water, the former making what is 
called a 50-per-cent, solution. A little lime is 
added to neutralize acidity. A 50-per-cent so¬ 
lution freezes at —15° F. 


The Automobile Handbook 


517 


Whether glycerine or calcium chloride is 
used, loss by evaporation should be made up by 
adding pure water, and loss through leakage by 
adding fresh solution. In using the chloride, 
it is important to prevent the solution from ap¬ 
proaching the point of saturation, as the chlo¬ 
ride will then crystallize out and clog the radi¬ 
ator, besides boiling, and failing to cool the 
motor. A 50-per-cent, solution has a specific 
gravity of 1.21, and should be tested occasion¬ 
ally by means of a storage-battery hydrometer. 
Equally important is it to prevent the water 
from approaching the boiling point, whatever 
tin* density, as boiling liberates free hydrochlo¬ 
ric acid, which at once attacks the metal of the 
radiator and cylinders. 

A solution of two parts of glycerine, one part 
of water, and one part of wood alcohol has been 
recommended, which is said to withstand about 
zero temperature. 

Certain mineral oils used for the lubrication 
of refrigerating machinery are recommended 
for cooling, because they remain liquid at very 
low temperatures. They are not particularly 
good heat conductors, however, and will not 
keep the motor as cool as the water solution. 
If the oil is used, it must be cleaned from the 
radiator by the use of kerosene and oil soap, 
before water can again be used effectively. 

As regards lubrication, the principal danger 
is that the oil will thicken from the cold so that 
it will refuse to feed. This is avoided by using 


518 


The Automobile Handbook 


cold test oil, which remains liquid at lower tem¬ 
peratures than ordinary oil, or by adding to the 
ordinary oil some kerosene or gasoline, and in¬ 
creasing the feed. If the oil tank is located 
close to the engine, it will remain liquid, even in 
quite cold weather. But unless the car has been 
kept in a warm place over night, the bearings are 
liable to run dry before the car has warmed up. 

Effect of Cold on Gasoline. The tempera¬ 
ture has a very marked effect on the rapidity 
with which gasoline vaporizes, and in cold 
weather it is necessary to supply heat to the 
carbureter. 

The carbureter should preferably be jacketed, 
and it may be warmed either from the circulat¬ 
ing water, or by taking a small quantity of the 
hot gases from the exhaust pipe. If water is 
used it should be taken from a point just be¬ 
yond the discharge of the pump, and should be 
delivered to the return pipe from the engine 
jacket to the radiator. 

Whether exhaust gases or water is used, the 
flow should be regulated by a cock, otherwise 
too much heat will be received in warm weather. 
When the carbureter is cold, the engine may be 
started by pouring warm water over it, care be¬ 
ing taken not to let any portion of the water 
get into the gasoline through any aperture in 
the top. Another method of warming up the 
carbureter is to wring cloths out of hot water, 
and wrap them around it. 


The Automobile Handbook 


519 


Fire for warming the carbureter or any other 
part of the motor should never be used. 

Oil and Gasoline Testing. In selecting gaso¬ 
line for any use, it is usually sufficient to know 
its density by Baume’s scale, this being the rat¬ 
ing at which it is sold in the general market. 
For instance, “Gasoline 72 Baume” means that 
the density of the gasoline is 72° of Baume’s 
hydrometer. Kerosene is generally rated by 
its flashing point. This point is the number of 
degrees of temperature to which it must be 
heated before the vapors given off from the sur¬ 
face of the oil will take fire from a flame held 
over the containing vessel. Thus, oil of 150° 
test is oil that will flash or take fire when heated 
to a temperature of 150° F. Kerosene, at or¬ 
dinary temperatures, should extinguish a lighted 
taper when the taper is plunged into it. 

Oil for Cooling. Oil can be used most effi¬ 
ciently to cool a motor in summer time, this 
having been conclusively proven in continuous 
tests in which oil was circulated through the 
water system at the same speed as water, and 
the motor gave considerably improved results. 
In recent experiments, although there was no 
trouble cooling water to the thermo-capacity of 
the radiator, yet when oil was passed through 
instead of water there was great disparity of 
results. One type of radiator, which cooled 
effectively with water, gave poor results when 
oil was used; in fact, the radiator giving the 
poorest results with oil gave best with water. 


520 


The Automobile Handbook 


and vice versa. From this it is evident that 
conditions must be altered when a change is 
contemplated from water to oil for cooling 
work. In one particular test it was found with* 
a temperature drop of 12 degrees with oil, the 
radiator gave a cooling effect of 700 cubic units, 
but when water was used, only 70 per cent as 
much heat was radiated, in spite of the fact 
that the air circulation was increased. In these 
experiments the radiators used were standard 
makes and designed for water use. These sev¬ 
eral tests, made by II. B. MacFarland, professor 
of applied mechanics and thermo-dynamics at 
Armour Institute, Chicago, indicated that the 
best radiators, when using oil, are 50 per cent 
more efficient than when using water. The ex¬ 
periments also proved that the engine was more 
efficient because it was possible to use the oil 
at a much higher temperature in the jacket 
without boiling than the water could be used at. 
The oil used in these tests was a very common 
grade of machinery oil bought at 12 cents a 
gallon. 

Oil Gun a Valuable Adjunct. A handy ap¬ 
pliance for the garage and even for the private 
owner is a large cpiiek action oil gun, which is 
easily made from an old bicycle pump by plug¬ 
ging up the outlet and drilling and tapping the 
bottom plate for a nozzle. The bottom plate 
can be cut down to the diameter of the pump 
barrel in case it has an extension to be held by 
the foot when pumping. Autoists will find such 


The Automobile Handbook 


521 


an oil gun as the above handy in many ways, as 
for quick filling of lubricators and scattered oil 
cups. It is very convenient also for sucking out 
the oil from the gearcase when a fresh supply is 
to be put in. This oil is usually too stiff to drain 
out, and as it is too full of steel chips to be al¬ 
lowed to stay in the gearcase, it must be re¬ 
moved in some manner. Obviously for such 



Fig. 250 


use the nozzle of the oil gun should be short 
and fairly large to permit the thick oil to enter. 

Oil Pipe Connection. The ordinary pipe fit¬ 
tings are not always reliable for oil and gaso¬ 
line pipes subject to vibration, and where the 
failure of a connection would involve serious 
consequences, as in racing engines, a better 
form of connection is desirable. Fig. 250 shows 
a special form of union devised by ( rane & 



























522 


The Automobile Handbook 


Whitman, of Bayonne, N. J., for important oil 
pipes. It is shown in service carrying oil to the 
under side of a main shaft bearing. The bot¬ 
tom cap A of the bearing is deeply ribbed and 
the oil duct is drilled in the rib. The connec¬ 
tion itself takes the form of an L-shaped steel 
union B, having a ground seat at C and brazed 
to the oil pipe at D. A special screw E passes 
through the union, and is threaded into the fur¬ 
ther side of the rib. The oil goes around the 
screw, and a lock nut and cotter pin insure 
against coming loose under even the most stren¬ 
uous conditions of service. 

Should an oiler reservoir begin leaking where 
one of the oil leads attach to it, the only suitable 
solution is the immediate soldering of it. The 
use of adhesive tape will sometimes suffice for 
a time, but the vibration generally renders it a 
poor repair. A small soldering iron is a most 
valuable part of a repair kit, and with it a sol¬ 
dering repair can be made in less than 20 min¬ 
utes. Oilers have been taken off, a fire built bv 
the roadside and the soldering done in less 
than 15 minutes, but the amateur who has not 
been accustomed to handling a soldering iron 
can hardly expect to do as expeditious a job 
as this, for, though a simple tool, considerable 
knack is required. 

Offset Crank Shafts. The practice of off¬ 
setting the crankshaft in automobile motors is 
rapidly gaining converts, and there are numer¬ 
ous examples of offsetting to be seen at the 


The Automobile Handbook 


523 


present time. In this scheme, it will be remem¬ 
bered, the crankshaft is not set in the plane of 
the middle of the cylinders. In other words, 
the crankshaft is set slightly to one side. The 
exact amount of this offset seems to be variable 



Fig. 251 

Section Through Engine with Offset Crank 

with different designers, but the object is al¬ 
ways the same. When the piston is in the po¬ 
sition of maximum compression involving the 
ignition and flame propagation, it is the idea 
to have the connecting rod in the vertical po- 






























































524 


The Automobile Handbook 


sition. The force of the explosion will then 
come on the connecting* rod endwise and the 
piston will not be pressed unduly against the 
cylinder walls. 

Offset Crank Shaft Engine—Timing the 
Valves. To time the valves of an engine hav¬ 
ing an offset crankshaft, the inclination of the 
axis of the connecting rod must be taken into 
account. As Figure 251 shows, the connecting 
rod is vertical, and if the shaft center were not 



Fig. 252 

Diagrams Showing the Four Positions of the Offset 

Crankshaft 


to one side, the flywheel would be marked at 
the exact center of the upper face, namely, at C. 
In the case where the center is set over, the rod, 
when in a vertical position as at G is not at 
the end of the stroke. If the flywheel were 
marked at C it would not indicate correctly the 
lower dead center. This does not appear until 
the three centers, piston pin, crank pin, and 
crankshaft are in line, as shown by the line 
D E F. The flywheel should be marked at this 

































The Automobile Handbook 


525 


point, and the mark may be on a vertical line 
through the crankshaft center or on a diagonal 
as the line just indicated. In the latter in¬ 
stance, the mark for the lower center would be 
at H. 

Similarly, the upper dead center, if marked, 
would be at a vertical point above the shaft 
center as C, but would assume a different posi¬ 
tion, located on a diagonal, as at A, on the cen¬ 
ter line ABE. 



Fig. 253 

Two-cylinder, Opposed Type, Engine 

Of course in actual timing, the upper and 
lower centers are not used, as good practice de¬ 
crees an overlap for the valve action, but they 
have been used as an illustration in this case be¬ 
cause their use simplifies the matter. 

In Figure 252, the actual marking of a fly¬ 
wheel is shown for a complete cycle. In this tin* 
angles selected follow the best modern prac¬ 
tice, being as follows: Inlet opens at 8 degrees 
past the upper center, and closes at 26 past the 



































526 


The Automobile Handbook 


lower center, giving an inlet opening, total, of 
198 degrees. Exhaust opens at 46 degrees be¬ 
fore the lower center and closes at 5 past the 
upper. This gives the whole angle for the ex¬ 
haust, 231 degrees on the crankshaft. 

As shown, the markings are put on the fly¬ 
wheel directly above the center of the crank¬ 
shaft, but the offset is taken into account. 

Opposed Cylinder Motor. The two cylinders, 
Fig. 253, are in the same plane with their open 
ends joined to a common crank case. As the 
two cranks are upon opposite sides of the crank¬ 
shaft, the two pistons are always moving in 
the same directions. 

The outward strokes are either compression 
or exhaust strokes, and the inward strokes are 
either suction or power strokes. Thus, during 
one-half turn of the crank-sliaft, one cylinder 
will be compressing while the other is ex¬ 
hausting. During the next, the first cylinder 
will be firing, and the second will be drawing its 
charge. During the third half turn the first 
cylinder will be exhausting and the second will 
be compressing, and during the fourth the first 
cylinder will draw its charge while the second 
is firing. It must be apparent that the two cyl¬ 
inders fire at periods one revolution apart, and 
upon the half revolutions when neither cylinder 
is firing, one of them is compressing. Thus, 
there is a power impulse in every revolution, 
and the action of the engine is shown in Fig. 
254. A flywheel of less weight is required to 


The Automobile Handbook 


527 


overcome the idle stroke than is found neces¬ 
sary in the single type to supply energy when 
no power is being developed. The moving parts 
are balanced and the explosion reactions alter¬ 
nate in that direction. 

The two-cylinder opposed motor is one of the 
best forms of two-cylinder motor, and is used 
extensively for motors up to about 16 horse¬ 
power. Since the cylinders are set end to end, 
with the crank case between them, the combi¬ 
nation is naturally rather long, and it is not 

POWER STROKE IDLE STROKE POWER STROKE IDLE STROKE 



Fig. 254 

Power Furnished by a Two-cylinder Engine 


practicable to employ this type of motor in 
anything but the horizontal position. 

Overheating—Causes of. Overheating of the 
engine, when not traced to poor circulation, is 
almost always caused by too much gasoline. 
There are, however, many possible causes of 
over rich mixture, some of which on the 
face of them might seem to be causes of lean 
mixture rather than rich. Prominent among 
these latter is too low a gasoline level in the 
float chamber due to the float valve closing too 
soon. The immediate effect of this is to make 
the mixture too lean at starting, and at low 












The Automobile Handbook 


speeds. Starting is therefore difficult, and if 
the auxiliary air valve begins to open at the 
usual motor speed, the mixture will again he 
much too lean. These symptoms, however, un¬ 
less properly interpreted will probably lead the 
owner to increase the gasoline supply, or to ad¬ 
just the spring tension of the auxiliary valve so 
that the latter will not open until quite high 
speed is attained. In other words, he adjusts 
to give a suitable mixture at one speed, and at 
other speeds the mixture is extravagantly over 
rich. It is well not to be too easily satisfied 
with the carbureter's performance, as it may 
be found that one fault such as the above has 
been imperfectly offset by another fault in the 
other direction instead of the correct adjust¬ 
ment being made where the fault really lies. A 
good carbureter will give a sensibly correct- 
mixture at all speeds within the ordinary range 
of the engine. If it fails to do this the thing to 
do is to investigate until the trouble is found. 

Insufficient lubrication increases the friction 
between the piston and cylinder, and so gener¬ 
ates extra heat. Bad or unsuitable oil may 
have the same effect. 

Wear of the cams, tappets and valve stems 
may be the cause of overheating, as it would 
not require much loss from the faces of the va¬ 
rious moving parts that come in contact to 
cause a more or less appreciable difference in 
the operation of the valves, and as this wear 
tends to bring about a later action, it may be 


The Automobile Handbook 


529 


sufficient in the case of the exhaust valve to 
retain the burnt charge considerably beyond 
the time at which it should be allowed to es¬ 
cape. Where a motor runs at a speed of 800 
revolutions per minute or over, it will be evi¬ 
dent that it is a matter of very small fractions 
of a second. 

Another cause of overheating may be the de¬ 
posit of a fine film of scale on the inside of the 
circulating pipes and radiator. This scale is of 
a mineral nature, and, in addition to being an 
excellent nonconductor of heat, it is deposited 
in such intimate contact with the metal that the 
latter is practically insulated and its radiating 
power entirely lost. 

Overheating—Effects of. The immediate 
effect of overheating is to burn up the oil in the 
cylinders, or crank case. This causes a smell 
of burning, and an or dor of hot metal. There is 
sometimes a slight smoke and the motor will 
make a knocking sound. The cooling water be¬ 
gins to steam, and the car will gradually slow 
down and finally stop. 

The most serious cause of a stoppage on the 
road is overheating, which causes the lubricat¬ 
ing oil to burn up and the piston to expand and 
grip or seize in the cylinder. 

Overheating—Remedies for. As soon as any 
of the above symptoms are noticed: 

The motor should be stopped at once. 

Kerosene should be copiously injected into 


530 


The Automobile Handbook 


the cylinders and the motor turned by hand to 
free the piston-rings. 

The parts should then be allowed to cool. 

Do not pour cold water on the cylinder jack¬ 
ets, for fear of cracking them, but pour the wa¬ 
ter into the tank so as to warm the water before 
it reaches the cylinder jackets. 

A simple test in the case of an overheated 
motor is to let a few drops of water fall on the 
head of the cylinder. If it sizzles for a few mo¬ 
ments the overheating is not bad, but if the 
water at once turns into steam, the case is seri¬ 
ous. 

Detach the spark plug or plugs, and turn the 
starting-crank slowly. This draws in cold air 
and cools the inside of the cylinder and the pis¬ 
ton. 

Packing. Packing or material for making 
gas, or water-tight joints is of various kinds. 
Asbestos packing comes in sheets, called asbes¬ 
tos paper or board, in the form of woven cloth, 
, and also as string or rope. Rubber packing is 
made in sheets, either plain or with alternate 
layers of canvas and rubber. Some forms of 
packing are known as Rubberestos, and Vul- 
cabestos, and are made of asbestos, impregnated 
with rubber and afterwards vulcanized. 

Paper Shims. Paper is a poor material for 
shims of any sort where pressures are high and 
intermittent, as in the bearings of the engine 
or gearcase, under the crankcase feet, or be¬ 
tween the gearcase and the frame. The principal 


The Automobile Handbook 


531 


excuse for using them is that they are so handy. 
On the other hand, they are liable to break and 
disintegrate from the pressure and vibration, 
and it is not always easy to squeeze them up 
tight enough in the first place to insure their 
staying where they are put. If they must be 
used they should be thoroughly saturated with 
shellac, and squeezed in place before the shellac 
dries. The shellac will act as a finger, and will 
also help the shims to cling. 

Parts, Extra. The necessity for carrying ex¬ 
tra parts upon a car becomes more apparent 
when a breakdown occurs miles away from 
home, and no material at hand to repair the 
break with. The accompanying list gives some 
of the parts generally needed in time of trou¬ 
ble : Bolts and nuts, chain links, dry batteries, 
extra valves, inner tube, insulated wire, pack¬ 
ing, spark plugs, split pins, sticky tape, valve 
springs, washers. 

Pierce-Arrow Six-Cylinder Motor Car. Fig. 
254a shows an open view of a Pierce-Arrow six- 
cylinder motor with chassis complete and ready 
to receive the body. The motor is composed of 
three twin cylinder units, and the crankshaft 
is of the seven bearing type, having journals of 
liberal diameter and length. Nickel steel, spe¬ 
cially hard treated is employed in the shape of 
a one-piece forging, machined all over, and ac¬ 
curately balanced and ground to a finish within 
the closest practical limit. This motor is car¬ 
ried on drop forged steel arms attached to the 



Standard Six-cvlinder, 48 Horse-power Pierce-Airow Chassis Complete. Ready to Receive the Body 





The Automobile Handbook 


533 


aluminum crankcase by long through bolts. 
At their ends these steel arms are bolted di¬ 
rectly to the pressed steel frame. The makers 
claim that there has never been a single instance 



of failure in this construction, which certainly 
speaks w T ell for its durability. Fig. 254b shows 
the rear axle, and connection between the 
clutch and gear set. In this connection two 
universal joints are used, in order to guard 















534 


The Automobile Handbook 



against any possibility of distortion, or depar¬ 
ture from a true alignment. The gear set is 
encased in an aluminum housing, supported on 
pressed steel cross members which are riveted 


to the side members of the frame. Chrome 
nickel steel of high tensile strength, and elastic 
limit is employed for both shafts and gears. The 
moving members are splined on the main shaft, 
while the corresponding pinions are bolted to 


o CC 
CM £ 


fee 

Q> 



The Automobile Handbook 


535 


flanges on the countershaft. The shafts are 
carried on Hess-Bright angular ball bearings of 
ample size to withstand the service. Speed con¬ 
trol is on the selective plan with the H-gate 
and side lever, the system being distinguished 
for simplicity, and certainty of action. As a 
preventive of unauthorized tampering, the 
gears cannot be meshed without disengaging 
the clutch. The positions of engagement and 
disengagement are determined by spring ac¬ 
tuated steel balls, seating in recesses in the 
shifting bars. 

Ignition. Dual ignition systems are fitted, 
and are independent throughout. A Bosch 
high-tension magneto is employed, the spark 
plugs being placed at the sides of the cylinders 
and directly in the inlet valve ports, while a 
set of six non-vibrating coils synchronized by a 
master vibrator, and supplied with current from 
a storage battery, comprise the emergency sys¬ 
tem, for which the plugs are placed over the 
inlet valves. The cooling water is circulated 
by means of a centrifugal pump driven by an 
independent shaft. The cylinders are of the 
T-head type with oppositely disposed valves ac¬ 
tuated by direct thrust from independent cam¬ 
shafts, the valve tappets being provided with 
fibre blocks, making the motor silent running. 

The Steering Pillar is a steel rod of liberal 
iliameter. At its lower end it has a multiple 
thread of extreme accuracy turned on it. A 
heavy drop forged steel block nut is threaded 


536 


The Automobile Handbook 


to correspond. Formed integrally with this 
nut are the arms of a trunnion, engaging hard¬ 
ened die blocks adapted to slide in the jaws of 
a forked lever. The nut is thus held from turn¬ 
ing, and the revolution of the steering pillar 
causes it to move up or down. This motion is 
multiplied and transmitted to the steering 
wheels through a series of levers. Spring cush¬ 
ioned joints are employed to absorb vibration, 
and a ball thrust bearing under the steering- 
pillar permits accurate adjustment for wear. 
This bearing is rigidly held by a special locking- 
device. The steering knuckles and spindles are 
one piece drop forgings of nickel steel. 

Final drive is by propeller shaft, a large uni¬ 
versal being provided at the forward end, and 
a universal slip joint at the after end of the 
shaft. 

The torsion rod is a triangle of seamless steel 
tubing, having its apex carried in a spring- 
cushioned, hinged joint, riveted to the after 
transverse member which supports the gear-set. 
At its base, the triangle is pivoted on a substan¬ 
tial bolt passing through the bevel gear hous¬ 
ing. 

The axle shafts are of heat-treated chrome 
nickel steel, and are directly attached to the 
wheels. The inboard bearing of the axle is of 
the Hess-Bright, annular ball type, while the 
outer one is a Timken roller-bearing, which 
possesses superior ability to withstand com¬ 
bined radial and thrust loads. This quality has 


The Automobile Handbook 


537 


been responsible for the adoption of the Timken 
bearings for the front wheels altogether. In 
the differential, and bevel gear drive, Hess- 
Bright bearings are fitted. 

The Brake. Whether it be more important 
for a motor car to run or to stop is something 
governed entirely by circumstances. Weight 
and speed have now reached a point where too 
much attention cannot be devoted to stopping 
ability. Good practice sanctions getting under 
way smoothly. But the necessity for stopping 
is governed by a time factor over which the 
driver frequently has no control. 

With each increase in size and weight, there 
should be a corresponding enlargement of the 
braking surface, and strengthening of the brake 
rigging, far in excess of normal requirements. 
The adoption of the three-quarter elliptic type 
of spring at the rear in connection with the 
drop frame, permits of a most effective ar¬ 
rangement of the drop-forged steel brake 
hanger. It affords the maximum leverage with¬ 
out any increased effort at the pedal or side 
lever. 

On the Pierce-Arrow cars, both the running, 
or pedal brake, and the emergency brake are 
located in special drums on the driving wheels, 
thus relieving the transmission of all braking 
stresses. The emergency brake is operated by 
the side lever, and causes the lined shoes to con¬ 
tract on the external faces of the drums. The 
pedal brake, acting through a heavy cam, ex- 


538 


The Automobile Handbook 


pands a similar set of shoes against the inner 
faces of the drums. This brake is intercon¬ 
nected with the clutch, disengaging the latter 
automatically before the brakes can act. In or¬ 
der that the motor may be employed as a 
brake, the emergency brake and clutch are not 
interconnected. The braking effort at the rear 
wheels is equalized by transverse compensators. 

Power Driven Air Pump. The modern type 
of Pierce-Arrow cars are now equipped with a 
power driven air-pump for inflating tires, and 
other purposes. This pump is located on the 
left-hand side of the motor forward, and is 
bolted directlv to the side member of the frame 

f 

in a vertical position. It carries on its shaft a 
large bronze gear, designed to mesh with a 
small steel pinion splined on the water pump 
shaft. To determine the positions of meshing 
and disengagement, a spring and ball device is 
employed. The small pinion is slid into en¬ 
gagement with the pump gear when the motor 
is stopped, and the latter is then run at from 
400 to 500 revolutions per minute, at which 
speed the pump will inflate the largest tires 
employed to a pressure of 90 pounds to the 
square inch in a few minutes. The pump is 
placed beneath the hood and is entirely out of 
the way when not in use, though so arranged as 
to be very accessible when wanted. 

Picric Acid. Gasoline will absorb or take up 
about 5 per cent of its weight of picric acid. 
The addition of a small quantity of kerosene 


/ 


The Automobile Handbook ■ 


539 


will enable the gasoline to absorb about 10 per 
cent of picric acid. 

Picric acid is only dangerous when fused, or 
when in a highly compressed state. 

An increase in motor efficiency of about 20 
per cent is claimed for the picric-gasoline mix¬ 
ture. 

About three-tenths of a pound of picric acid 
is required for each gallon of gasoline. The 
mixture should be allowed to stand for two 
days, agitating occasionally during this time, 
then strain through two or three thicknesses 
of very fine muslin before using. 

It must be remembered that picric acid is an 
etching ingredient, which is another way for 
saying that it will destroy the cylinder walls. 

The explosive force of picric acid is very 
much overrated. If thrown upon a red hot 
plate of iron, it simply burns with a smoky 
flame, and striking a small quantity of it upon 
an iron anvil will not explode it. 

Pipe Nipples. Nipples are always ordered by 
the nominal diameter of the pipe, and the over¬ 
all length of the nipple. Table 15 gives the 
standard lengths of nipples of varying diame¬ 
ters, also the number of threads per inch and 
the outside diameter of the pipe. 

Pistons. The piston used in a gasoline motor 
cylinder is of the single-acting or trunk type. 
It is made of an iron casting which is a good 
working fit in the cylinder. Around the upper 
end of the piston three or four grooves are cut. 


540 


The Automobile Handbook 


and in these grooves the piston-rings fit. The 
rings are made of cast iron, and the bore of the 
ring being eccentric to its outer diameter, there 
is a certain amount of spring in them, and so 
pressure is caused against the cylinder wall, 
preventing any of the expanding gases passing 
the piston. 

The lubrication of the piston-rings is very 
important, for on that depends the proper work- 


TABLE 15. 

LENGTH OF STANDARD PIPE NIPPLES. 


Nominal 

Diameter. 

Outside 
Diameter 
of Pipe. 

Threads 
per Inch. 

Over-all 

Length of 

Nipples. 

Close. 

Short. 

Long. 

\ 

Vs 

.40 

28 

% 

1% 

2 | 2i/ 2 

3 

31/2 

% 

.54 

18 

% 

1% 

2 1 21/2 

3 

31/2 

% 

.68 

18 

1 

1% 

2 | 21/, 

3 

3i/ 2 

% 

.84 

14 

1% 

1% 

2 1 21/2 

3 

31/2 

% 

1.05 

14 

1% 

2 

21/2 1 3 

31/2 

4 

1 

1.32 

11 

1% 

*> 

2% 1 3 

3% 

4 

1% 

1.66 

11 

1% 

2% 

3 1 31/2 

4 

41/2 

1 % 

1.90 

11 

1% 

2% 

3 1 31/2 

4 

41/2 

2 

2.38 

11 

2 

2% 

3 1 31/2 

4 

41/2 


iug of the piston in the cylinder. In single 
cjdinder motors, the piston-rings require fre¬ 
quent attention, and kerosene should be in¬ 
jected into the spark plug opening at frequent 
intervals. Occasionally the cylinder should be 
taken off, and the rings cleaned with a brush 
and kerosene. In multi-cylinder motors, this 
constant attention is not required, for in addi¬ 
tion to the splash system of lubrication, usually, 
there are pipes leading to the cylinders, 




















The Automobile Handbook 


541 


through which oil is fed and so keeps them well 
lubricated. The speed of the motor being so 
much less, there is no danger of the oil being 
used up rapidly. 

Piston Displacement. The piston displace¬ 
ment of a motor is the volume swept out by the 
piston, and is equal to the area of the cylinder 
multiplied by the stroke of the piston. The 
expression, cylinder volume, is sometimes con¬ 
founded wtih the term piston displacement. 
This is erroneous, as the cylinder volume is 
equal-to the piston displacement, plus the com¬ 
bustion space in the cylinder head. 

Pistons, Length of. For vertical cylinder 
motors the length of the piston should not on 
any account be less than its diameter, while a 
length equal to one and one-quarter or even 
one and one-third diameters is better. For mo¬ 
tors with horizontal cylinders the length of the 
piston, in any case, should not be less than one 
and one-third diameters, and if possible one 
and one-half diameters or over. 

Piston Position. There is nothing more con¬ 
fusing to many motorists—not only to the be¬ 
ginner, but to many who are proficient in the 
general care and operation of their motor cars 
—than the relative various positions, in a four¬ 
cycle engine, of the four pistons on any of their 
four cycles of compression, work, explosion, 
and exhaust, this being the order of the cycles. 

In the following illustrations the pistons are 
shown as they are usually placed in relation to 



The Automobile Handbook 


Fig. 255 Fig. 256 











































































































































The Automobile Handbook 


543 



Fig. 257 Fig. 258 























































































































































The Automobile Handbook 


544 


one another. That is, pistons 1 and 4 are at 
the top of their strokes when pistons 2 and 3 
are at the bottom, and, obviously, vice versa. 
The figures over the pistons in each diagram 
represent their order of number, counting from 
either end of the engine. 

In Fig. 255, cylinder I is ready to descend 
on its intake stroke—having finished its ex¬ 
haust stroke—and cylinder 4 is ready to de¬ 
scend on its working stroke—having finished 
its compression stroke. Cylinders 2 and 3 are 
ready to move on their up strokes, No. 2 on its 
compression, having finished its intake, and 
No. 3 on its exhaust, having finished its working- 
stroke. The results are that the pistons are 
brought into the positions shown in Fig. 256. 
This means that cylinder No. 1, having com¬ 
pleted its intake downward stroke, is ready for 
its compression up stroke; No. 2 has moved up 
on compression and is ready to go down on 
work; No. 3 has finished exhausting and is 
ready for intake and No. 4 has finished the 
work stroke and is ready to move up on ex¬ 
haust. Piston No. 2, having completed its work 
stroke, the pistons are brought back to the po¬ 
sitions shown in Fig. 255, but with an altered 
condition of the cycle represented by each, as 
shown in Fig. 257. The pistons are now ready 
to move to the positions shown in diagram 2, 
with an altered cycle condition. Cylinder No. 
1 moves down on work; No. 2 up on exhaust; 


The Automobile Handbook 


545 


No. 3 up on compression and No. 4 down on in¬ 
take, see Fig. 258. 

When the cycle of each has been completed, 
from the above starting points of No. 1, ex¬ 
haust; No. 2, intake; No. 3, work, and No. 4, 
compression, the pistons are then back not only 
in the position of Fig. 255, but with the same 
condition of cycles. 

This explanation has been in the order of the 
cylinder numbers, but the effect of each cycle 
of each cylinder will be easier traced if it be 
remembered that the order in which the cylin¬ 
ders work is: Cylinder 1, then cylinder 3, then 
cylinder 4, and then cylinder 2, and then repeat 
indefinitely. From this and the above illustra¬ 
tions it will be easily understood that as piston 
No. 1 goes down on its work stroke, No. 3 
comes up on compression stroke, and is then 
ready for the work, which is a down stroke 
bringing No. 4 up on compression. No. 4 then 
goes down on work and brings No. 2 up on com¬ 
pression, then it goes down on work and brings 
No. 1 up on compression for the repeating of 
cycles. This shows that each synchronized pair, 
1-4 and 2-3, always have one cycle between them 
as they move together, either up or down. 

Piston-Rings. To ensure proper compression, 
it is absolutely essential that the piston-rings 
should be kept lubricated; consequently when 
the motor has been idle for some time, the 
compression at the start is often poor. Any fail¬ 
ure in the lubrication while running will, of 


546 


The Automobile Handbook 


course, have the same effect, such, for example, 
as in the case of overheating, or when the sup¬ 
ply is intermittent. Sometimes the piston- 
rings get stuck in their grooves with burnt oil, 
through overheating, and the compression es¬ 
capes past them. Thorough cleaning with kero¬ 
sene, and fresh lubricating oil will settle the 
matter. In motors where the rings are not 
pinned in position, the slots may work round so 
as to coincide. In this case they will have to be 
moved around. Sometimes burnt oil may, ap¬ 
parently, have the opposite effect on piston- 
rings, for by causing the piston to grip in the 
cylinder, it will produce considerable resist¬ 
ance, and the operator might erroneously think 
in consequence that his compression is good. In 
every case, after a long run, a little kerosene 
should be injected into the cylinders to clean 
the rings. 

Piston-Rings—Method of Turning. A pat¬ 
tern should be made from which to cast a blank 
cylinder or sleeve with two projecting slotted 
lugs on one end to bolt same to face plate of 
lathe. This blank should first be turned off out¬ 
side to the required diameter, making it, of 
course, sufficiently larger to allow for the cut 
in the rings, after cutting from the blank. The 
blank should then be set over eccentric suffi¬ 
ciently to allow the thick side of the rings to ba 
twice the thickness of the thin side after turn¬ 
ing. The inside of the blank can then be bored 
out, and the rings cut off to the exact thick- 


The Automobile Handbook 


547 


ness required with a good sharp cutting off tool. 
A mandrel or arbor shoud be made with two 
east iron washers or collars to fit on it, one fas¬ 
tened to the mandrel and the other loose, with 
lock nut on mandrel with which to tighten up 
the loose collar. After the rings have been 
sawed open and a piece cut out the required 
length, they can be placed in a collar or ring 
about 1-32 to 3-64 of an inch larger than the cyl¬ 
inder bore, and slipped on to the mandrel one 
at a time of course, with the loose collar and 
nut off the same. The loose collar and nut can 
then be put on the mandrel, the ring clamped 
tightly between the two collars, the mandrel 
put in the lathe and the ring turned off, without 
leaving any fins or having to cut the ring off 
afterward as is done in many cases. This is the 
only way in which a perfectly true ring can be 
made. 

Piston Velocity, Limitation of. The speed of 
rotation of an explosive motor is limited by the 
fact that the velocity of the piston must be con¬ 
siderably less than the rate of combustion of 
the explosive mixture, in order that the motor 
may develop energy or do work. The practical 
limit of piston velocity is said to be between 14 
and 16 feet per second. 

Piston Head Scraper. In most engines the 
piston heads can be scraped clean of carbon 
without removing the pistons from the cylinders, 
by means of specially formed scrapers intro¬ 
duced through the opening over the valves, or 


548 


The Automobile Handbook 


through the spark plug holes when the latter 
are horizontal. The form and size of scraper 
will depend on the particular engine, but al¬ 
most anv suitable form may be made from 5-16- 
inch steel tubing about 12 inches long hav¬ 
ing the ends hammered hat, and turned over at 
right angles in a vise. The ends are then 
filed straight, and sharp, and the shank of the 
scraper may be bent to right or left, if neces¬ 
sary, or left straight. Frequently two scrapers 
will be needed in order to use both right and 
left hand bends. The advantage of tubing for 
this purpose is that no blacksmith work is nec¬ 
essary. 

Platinum. The contact points of the vibrator 
of an induction coil should always be of plati¬ 
num. German silver or any other metal spoils 
the quickness of the break on account of the 
greater tendency of the contact-points to car¬ 
bonize, when of any other metal than platinum. 
Spark plug points should also be of platinum 
or iridio-platinum, which is better yet, as it is 
more capable of withstanding the intense heat 
in the combustion chamber than the platinum 
itself. Any other metal than platinum (except 
gold) will turn green or black if tested with 
nitric acid. 

Polarity. To ascertain the polarity of the 
terminals of a storage battery or light circuit, 
place the ends of the wires on the opposite ends 
of a small piece of moistened litmus paper. The 


The Automobile Handbook 


549 


wire on the side of the paper which has turned 
red is the negative pole of the battery. 

Porcelain. Porcelain tubes used for the in¬ 
sulation of the center rod of a spark plug have 
higher insulative properties than lava or mica, 
but on account of the liability of the porcelain 
to break from too sudden change of tempera¬ 
ture, it is not as reliable as other forms of in¬ 
sulating material. 

Pounding—Causes of. The most obvious 
cause of pounding is that of a spark advanced 
too far. This, however, nearly always occurs 
upon hills, in deep sand or mud, or elsewhere, 
whenever the engine is laboring very hard. In 
the case of too far advanced spark, manipula¬ 
tion of the spark would only make the pound 
worse than ever. So, too, if the spark was nor¬ 
mally set too far advanced, it would pound 
more at high speeds than at slow, just the re¬ 
verse of the actual case. 

Preignition causes pounding, and is itself 
caused by overheated piston or cylinder walls. 
Glowing points or deposits of carbon within 
the cvlinder, as well as faulty or uncertain igni- 
tion also cause it. Leaks in the chamber are 
sometimes the cause of pounding, so too, are 
looseness of parts. Among the latter may be 
cited: connecting rod bearings, main bearings, 
loose flywheel, cracked flywheel; other lost mo¬ 
tion. Beyond these things, the only other cause 
of pounding is that of some moving part which 
strikes as it rotates. 


550 


The Automobile Handbook 


Preignition—Causes of. If the inside sur¬ 
faces of the combustion chamber are free from 
sharp corners or projections formed in casting’, 
preignition is probably due to the combined in- 
fluences of high compression, and carbon or dirt 
on the piston head. Next to the exhaust valve 
itself the piston head is the hottest part of the 
engine, since it cannot be water cooled. For 
this reason it is much more important to keep 
the piston head clean than the other surfaces 
exposed to flame, and this is best accomplished, 
first, by the use of a good non-carbonizing oil, 
and, second, by thoroughly screening the air 
intake. If preignition is troublesome it will 
pay to fit a dust screen underneath the engine 
in case none is already provided, since what¬ 
ever dust touches the piston head will be held 
there by the oil, and will be fully as effective in 
causing preignition as the same amount of 
carbon. The intake itself should draw air 
through at least one, and preferably two or 
more fine wire gauze screens of sufficiently large 
area to permit the air to pass through them 
slowly. These screens should be removable, and 
should be inspected, and cleaned with gasoline 
and a toothbrush as often as may be necessary. 
It will be found that the fitting of a suitable 
dust screen beneath will make an immense dif¬ 
ference in the amount of cleaning, which the 
gauze screens require. In the manufacture of 
high classed motor cars the greatest care is 
taken in scraping the walls and dome of the cvl- 


The Automobile Handbook 


551 


inder castings forming the combustion space, 
the aim being to remove every projection that 
might cause a pre-ignition point as alko to re¬ 
move every burr, or rough spot to which for¬ 
eign matter would adhere. The lubrication 
system of a car is a most important factor in the 
elimination of preignition due to the proper 
amount of oil being fed to the cylinders at all 
times. 

Pump Lubrication. Grease is the proper lu¬ 
brication for a pump, and it should be stiff 
enough so that the water will not wash it away. 
Be careful not to use too much, as highly heated 
water tends to carry it into the radiator and 
deposit it there, where it is liable to clog the 
circulation, or at least reduce the efficiency of 
the radiator. 

Pumps—Centrifugal. In this type of pump 
the height of lift is governed by the tangential 
force. Owing to this fact centrifugal pumps for 
use on automobiles may be made of aluminum 
for the housing, as it is both light and strong, 
fully able to withstand the pressure, there being 
no rubbing surfaces. The wheel, however, 
should be made of phosphor bronze of a good 
grade. In these pumps the suction inlet is 
usually at one side surrounding the axis, see 
Fig. 259. The pump should be geared to a speed 
as high if not higher than the crankshaft speed. 
The minimum peripheral velocity of the pump 
wheel should be 500 feet per minute. For au¬ 
tomobile service the general rule is to have a 


The Automobile Handbook 



Fig. 259 

Section of a Centrifugal Water Pump, Showing Entrance 
of Water at the Side, Around the Shaft 

circulating system, look for a blockage of the 
circulation, or failure of the pump. 

If some of the radiator tubes are cool and 
others are hot, look to the pump. 

To test the pump before starting, run the 
motor for a few minutes. Then ascertain how 


three vane wheel, and the curving is away from 
the direction of rotation. 

Pumps, Water Circulating. If steam is seen 
coming from the relief, or outlet of the water 











































The Automobile Handbook 


553 


long it takes before the top radiator tubes are 
thoroughly hot. If the heat of the pipes is uni¬ 
form the circulation is all right. 

Radiator—Water-Cooling. The design of a 
radiator should be such that the maximum of 
surface is exposed to the air and the greatest 
freedom afforded for the circulation of the wa¬ 
ter. As a circle presents the minimum surface, 
it would appear that a circular pipe is not the 
best shape for a radiator tube. There are, how¬ 
ever, many reasons in favor of the circular sec¬ 
tion, one of which is the small resistance offered 
to the flow of the water. With a circular shape 
the minimum weight of tube is obtained for a 
given cubic content of liquid, and the greatest 
strength also for a given weight. A flattened 
tube section is often used, and is made up to 
represent in appearance the cellular radiators 
which have recently come into use. If the cel¬ 
lular radiators are well made, they have the ad¬ 
vantage of being more easily cleaned of mud 
than any other design. The number of joints 
forming a honey-comb radiator are likely to be 
a cause of leakage, and such a radiator is far 
more difficult to repair on the road than the 
tubular type with radiating fins or discs. 

Radiator, Cooling Surface Per Horse¬ 
power. ]\Totors using the thermo-siphon or 
natural water circulation require about 5 
square feet of radiating or cooling surface per 
horsepower. 

Radiator—Combination Water Tank. Four 


554 


The Automobile Handbook 


styles of combination water tank and ra¬ 
diator are shown in Figure 260, having vertical 
cooling tubes with radiating discs, honey-comb 
or cellular form of radiation and horizontal 
tubes, respectively. 

Radiator Cap Stuck. The commonest cause 



Fig. 260 


of a radiator cap sticking is simply expansion 
of the threaded ring on which it screws. In 
other words, it sticks only when hot, and is un¬ 
screwed easily when cold. The time to refill the 
radiator therefore is before rather than at the 
end of a run. If, however, refilling is necessary 
when hot, for instance, after a stiff hill-climb, 




































































The Automobile Handbook 


555 


the simplest plan is to cool the top of the radia¬ 
tor and the base of the ring under the cap by 
pouring water thereon, being careful not to get 
the water on the cap itself. 

Repairs—Tools for. In Fig. 261, three types 
of valve lifters are shown. B and C are of the 
same principle, and quite efficient in almost any 
case; but A, when properly operated, and on 
its respective motor, is more quickly applied, 



and consequently a time saver. D is a valve- 
seating tool, supplied as special equipment by 
one of the large motor car manufacturers. 

In Fig. 262 are shown a couple of spanner 
wrenches and one or two other tools that are 
quite uncommon but quite necessary in the work 
to which they are adapted. A is made from a 
piece of steel tubing and used on packing 
glands—the tube to slip over the shaft—and the 
small lugs at the end engage corresponding 





























556 


The Automobile Handbook 


recesses in a packing nut. B is representative 
of a valve-grinder, designed especially for the 
valves in certain motors. The spanner C is re¬ 
quired to conveniently remove certain types of 
cylinder plugs; while D, which approaches the 
conventional, is used in adjusting bearings of 
a particular type. 

There is probably a greater variety of wheel 
and gear pullers now in service than of any 



other special tool. In Fig. 263, A looks very 
much like the standard adjustable wheel and 
gear puller for sale in all supply houses; and 
it practically is the same except that the hooks 
are larger and twisted in opposite directions 
and at right angles to the beam. It is found 
useful in removing road and flywheels and the 
like. B is a non-adjustable tool made especially 
for removing flywheels. C and P are road wheel 
pullers, and are included in the regular equip- 





The Automobile Handbook 


557 


ment of tools supplied with the cars of two 
prominent manufacturers. C is part of the 
Rambler tool equipment and is used in connec¬ 
tion with their spare wheel; and P represents 
the type of wheel puller supplied by the Pierce- 
Arrow. E is a gear-puller designed to remove 
the half-time-gears of an Oldsmobile, the two 



Fig. 263 


side-screws being intended to fit into threaded 
holes in the web of the gears. 

When the Jack is Missing. Should the jack 
be missing or broken, an efficient substitute can 
be rigged from a large stone or a number of 
bricks piled one on another until the height is 
sufficient to lift the wheel from the ground. 





























558 The Automobile Handbook 

Having gotten the stone or piled the bricks one 
of the floor-boards can be utilized as an inclined 
plane and the car backed up until the axle rests 
on the top of the pile. When the work has been 
performed, the axle will have to be pushed off 
the pile, but as the drop is inconsiderable no 
harm can come to the tire. Where stake-and- 



Fig. 264 

Removing Dent in Gasoline Tank 


rider fences abound, one of the rider timbers 
can be utilized as a lever, with a stone as a ful¬ 
crum to raise the axle, supporting the latter 
with another stone during the repair, and gently 
easing down the axle when ready to proceed. 

Removing Dents. An easy method of remov¬ 
ing dents consists of soldering a piece of wire 
to the bottom of the dent, then pulling the de- 

























The Automobile Handbook 


559 


pressed portion out to its proper position. When 
the dent happens to be in an oil, or gasoline 
tank, or a radiator, an old valve can be most 
effectively used in place of the wire, as shown 
in Fig. 264. The top surface of the valve is hied 
smooth and bright, then cleaned with soldering 
acid and tinned with solder. A fiat surface of 
the same area, and as near the bottom of the 
dent as possible, is treated in the same manner, 
and the valve sweated on. This sweating on is 
done by placing the prepared portion of the 
valve against the tinned surface of the dent, 
and then applying heat with a torch till a fu¬ 
sion of the solder takes place. The heat should 
then be removed and the solder allowed to set. 
When cool, it will be found that with the valve 
stem as a handle and lever, and probably a few 
light taps with a hammer around the edge of 
the dent, the deformed part can be most easily 
straightened out. 

Reversing—Backing Up. Among other things 
connected with driving which is apt to be neg¬ 
lected, is reversing, or driving a car backward. 
Usually a car is never reversed for more than 
a few yards at a time and the maneuvering in¬ 
volved requires no great skill. Steering a car 
when running backwards is diametrically op¬ 
posite to that when running forward. A turn 
of the wheel to the left steers the car in the 
opposite direction to the right, and vice versa. 
The usual mistake made in reversing is in turn¬ 
ing the steering wheel too far, and describing 


560 


The Automobile Handbook 


zigzags m the road as a result. The autoist 
should remember that the reverse gear of a 
sliding change gear should never be engaged 
until the car has been brought to a full stop. 

Rheostat. A rheostat is a device for regulat¬ 
ing the how of current in a closed electrical 
circuit, by introducing a series of graduated 
resistances into the circuit. 

Rubber, India. All articles made of com¬ 
mercial rubber should be kept from contact 
with oil, kerosene, gasoline or grease if they 
are to be kept in good condition. Vulcanized 
rubber should not be exposed to a temperature 
of more than 130 degrees, Fahrenheit. Com¬ 
mercial or vulcanized rubber contains not to ex¬ 
ceed 30 to 35 per cent of pure India rubber, as 
its stretching quality, stickiness and rapid dete¬ 
rioration under the action of light and air make 
its sole use undesirable. 

Rubber Cement, How to Make. Marine glue, 
so-called, is an excellent cement. This consists 
of one pound of caoutchouc to one gallon of coal 
tar naphtha, and twenty pounds of shellac. 
Heat gently and pour on metal plates to solidify. 
When needed, melt. By using more naphtha, 
this is made thinner so as to stay liquid. The 
sulphur in this is in the caoutchouc, but if found 
insufficient in any one case, more sulphur may 
be added to the cement in the powdered form, 
when making it up, or if necessary, when re¬ 
molting. 

Another excellent cement is gutta-percha 


The Automobile Handbook 


561 


Cement. The composition of this is two parts 
of gutta-percha to one part of common pi ten. 
It is melted together, and well-stirred in the 
melting, the stirring being fully as important 
as the materials. When thoroughly melted and 
stirred, it is poured into cold water. This makes 
it into a hard brittle substance, which softens 
at a low temperature, and at 100 degrees is a 
thin fluid. Like the former recipe, this carries 
its own sulphur in the gutta-percha, but if more 
is necessary, it can be added as a powder. In 
this ease, it is not advisable to add the sulphur 
during the remelting process, but it should be 
put in while making up a batch of the cement. 

As a rule, as little cement should be used as 
is possible to make a good job. Moreover, all 
cement should be given plenty of time to dry. 
Rubber surfaces to be united should be thor¬ 
oughly cleaned, either with naphtha or with a 
thin cement. When the latter is used, it is 
brushed over the surface very lightly, using a 
fine brush, and then the surfaces are heated 
gently. This helps the whole operation, because 
it both softens the rubber, and evaporates the 
solvent, which is then unnecessary to complete 
the operation, having served its usefulness. 

In addition to the various substances men¬ 
tioned before for cements, it is very often neces¬ 
sary to have the cement dry very rapidly. In 
these cases, specific driers are added, and may 
usually be added to any cement at will, the 
quantity added being measured only by the re- 


562 


The Automobile Handbook 


quired speed in drying. Then there are cases 
where certain degrees of tenacity are required. 
For these, other gums are added, as rosin, mas¬ 
tic, gumlac, etc. These, however, should be 
used only when needed, and much discretion 
should be used in adding them to an already 
very satisfactory cement. 

Running Gear. A complete running gear in¬ 
cludes the frame, springs, wheels, motor, speed- 
change-gear, axles and the machinery of the 
car except the body. The French word, chassis, 
is sometimes used to designate a running gear, 
but its use is not correct, as strictly speaking 
the term, chassis, applies to the frame only, or 
at the most to the frame and springs. 

Figure 265 illustrates a vertical section of a 
running gear equipped with a vertical four-cyl¬ 
inder motor, and longitudinal propeller-shaft 
drive, by bevel gearing to the live rear axle. 

A plan view of a running gear with double 
side-chain drive and rigid rear axle is shown in 
Figure 266. The motor is also of the vertical 
four-cylinder form. The water cooling system 
in both cases is by rotary pump, combination 
tank and radiator, and fan, as shown. 

Scratched Cylinder. The cylinder may be 
temporarily fixed by taking it to a first-class 
tinsmith and having the scratches filled with sil¬ 
ver solder. The soldered places must be then 
carefully scraped Hush with the bore of the cyl¬ 
inder. The best way is to have the cylinder re¬ 
bored and the piston-rings re-turned. 


The Automobile Handbook 


563 




RUNNING GEAR 






















































































Fi^. 2 (>0 


























































































































































The Automobile Handbook 


5 65 


If the scratches are not too deep the cylinder 
can be rebored,, and a new set of piston-rings 
made to fit the new bore. The limit to such an 
increase in bore is about one-sixteenth of an 
inch. 

Screw-Driver, Uses of. A screw-driver is 
one of the handiest and most useful tools on a 
car. It can be used to grind in a valve, to press 
a valve spring out the way, or to hold a valve 
spring up while the spring cap is being put on. 
It may also be used as a chisel to tighten a 
loose nut, which otherwise cannot be gotten at. 

Secondary Current. The current which takes 
its rise in the fine wire of the induction coil, and 
which flows through the wire to the spark plug, 
is induced in the fine wire by the sudden rever¬ 
sal of the magnetism of the iron core. 

This change of magnetism is caused by the 
sudden interruption of the primary current. 

Self-firing, Causes of. If the motor should 
continue to run after the switch has been 
opened, it is due to an insufficient supply of 
lubricating oil, causing the motor to overheat, 
or to the presence of soot or some projection in 
the combustion chamber becoming incandes¬ 
cent. It mav also be due to lack of water or 
to the water circulation working poorly, caus¬ 
ing the motor to overheat. 

Shaft Drive. The principal advantages which 
may be advanced for the shaft drive are, absence 
of noise, convenience with which all the parts 
may be housed in oil and protection from 


566 


The Automobile Handbook 


dust. It is especially adapted for use upon cars 
carrying their engines in front, with the crank¬ 
shafts parallel with the length of the car, as the 
direction of the power shaft does not have to 
be changed until the rear axle is reached, and 
as the power must also pass through one set of 
bevel gears* it is more efficient. 

The principal disadvantages of the shaft 
drive are that it is difficult to repair; it is some- 



Fig. 267 

Pouring Parson’s Metal 


what more complicated; it has considerable 
end-thrust and it is claimed that it is harder on 
the tires. 

Shop Kinks. To reline a journal box with 
Parson s white brass, proceed as follows: Pre¬ 
pare a reasonably smooth cast iron plate A, Fig. 
267. which is bored to receive a vertical man¬ 
drel B about 3/16 inch smaller in diameter than 
the finishing bore of the box. An annular brass 
ring C, about % inch wide, and whose in- 
















The Automobile Handbook 


567 


side diameter is about % inch smaller than 
the outside diameter of the end flange D 
of the box to be lined, is then located on 
the iron plate concentrically with the man¬ 
drel, and secured by means of pins or other¬ 
wise. This ring serves as a support for the 
box itself, and in the process of pouring, the 
space between the ring and mandrel is filled 
with white brass which is afterward turned off. 
Any imperfect metal which may be poured will 



Fig. 268 


find its way either into this space or into the 
space above the box, leaving the lining of the 
box itself perfectly sound. The box itself is 
assumed to have been suitably eounterbored 
and recessed to hold the lining as shown in the 
sketches E and F, Fig. 268. It is preferable to 
use the arrangement shown at F and allow the 
lining to extend beyond the ends of the box, and 
form the outer surface of the flanges. In this 
case the diameter of the flange formed by the 
lining will be the inside diameter of the sup- 























568 


The Automobile Handbook 


porting; ring, which will be slightly smaller than 
the diameter of the flange of the box itself. 

The halves of the box—if it is split—are 
wired together and the box and the mandrel are 
heated by torches and assembled as shown in 
the sketch. A second ring—not shown—simi¬ 
lar to the supporting ring is placed on the top 
of the box, and .all the cracks are luted with 
moist fire clay. Meanwhile, the white brass 
has been melted in a kettle to a fairly high 
heat somewhat higher than the pouring temper¬ 
ature. While it is being melted, it is kept cov¬ 
ered by about 1 inch of powdered charcoal, 
which excludes the air. When the maximum 
temperature is reached, the charcoal is quickly 
skimmed off and a handful or two of powdered 
salammoniac is thrown on. The salammoniac 
is immediately volatilized and forms a heavy, 
though colorless gas which shuts off the air 
from the surface of the metal and causes it to 
stay bright. The pouring is then done with all 
possible haste, and on cooling the metal will be 
found perfectly homogeneous and solid. If the 
box is split the lining can be condensed by pen- 
ing. If the box is solid, the lining is simply 
bored to the proper size. 

To Restore a Sagged Frame. A frame which 
is sagged to the extent of permanent deforma¬ 
tion can be restored so as to approximate its 
original shape, by heating it in a charcoal fire 
with an air blast. To do this properly, it will 
most likely be necessary to cut out the rivets, 


The Automobile Handbook 


569 


so that the side members can be handled inde¬ 
pendently. xV good plan of procedure is to in¬ 
close the bent portion of the frame in a section 
of stovepipe of sufficient size in which the char¬ 
coal fire is built. A length of 1-inch gas pipe,, 
closed at one end, and having 5/16-inch holes, 
drilled at intervals of about 6 inches, is laid in 
the bottom of the pipe and furnishes the air 
supply from a bellows. When the charcoal fire 
is well kindled, the frame is introduced upside 
down, and is supported at the ends. The fire is 
then concentrated on the bent portion, and as 
the frame becomes hot it will straighten itself. 
It, must be watched carefully and the air blast 
stopped as soon as the frame is seen to be 
straight. Most of the frames used in American 
cars are ordinary carbon steel, and require no 
special treatment. It will be well, however, on 
stopping the air blast to shift the stove pipe to 
a cooler portion of the frame, to permit the 

0 

part which has been straightened to cool as 
quickly as exposure to the air will permit. A 
frame which has been sagged and straightened 
in this manner will require to be trussed to pre¬ 
vent recurrence of the trouble. As conditions 
vary so much the best rule to follow is to ob- 
serve the truss arrangement on some similar 
car. The struts should be about 4 or 5 inches 
long, and should be located at the spots where 
the sagging has occurred. The truss rod itself 
should be about V 2 inch in diameter, and drawn 
taut by a turnbuckle, which may be finally 


570 


The Automobile Handbook 


tightened when the chassis has been assembled. 

Spanish Windlass. The old fashioned Span¬ 
ish windlass, in Fig. 269, may be occasionally 
employed where no other hoist is available. It 
is extremely handy in setting, and lining up 
motors, transmissions and rear axles. It con¬ 
sists of a round bar or piece of pipe, a piece of 
r ‘ope, and a lever such as -a small crowbar or 



jack-handle; all of which are quite common to 
the ordinary repair shop. The round bar is 
laid across the side members of the frame, the 
rope is made fast to the object to be hoisted, a 
loop of it is wound around the bar as shown, 
and the lever inserted in the end of the loop. 
Although this is as old as the hills, it is not un¬ 
common to see a man lying on his back, in a 






The Automobile Handbook 


571 


most uncomfortable position, holding a heavy 
transmission case up into place while another is 
trying to locate the bolt holes, and adjust the 
liners; whereas, if this makeshift windlass were 
employed, one man could raise and set the gear¬ 
box with much less trouble. 

Straightening Spindles. In Fig. 270 a tool 
is shown which is used in a local repair shop, 
for straightening spindles. The tool, which is 
of heavy construction, is placed in a vise; the 



spindle is heated to a red heat, the ends cooled 
off with water, and placed between the centers, 
as illustrated. A lever is then placed between 
the bent portion of the spindle and the shank 
of the tool, so that when pressure is brought to 
bear on it, the spindle arm may be brought 
back into its normal position. 

Cleaning Aluminum. Aluminum, such as 
used for foot-boards of cars, may be cleaned by 
using hyposulphate of soda, as this substance is 
a solvent of aluminum tarnish. The dirty sur- 







572 


The Automobile Handbook 


face should be washed with a strong solution 
of the hyposulphate; then rinse the surface with 
water and dry. 

Care of Tire Pump Leather, The proper 
lubricant for the cupped leather washer of the 
tire pump xuston is vaseline. Oil is too thin 
and it tends to work into the rubber hose, and 
even into the tire itself if too much is used. Vas¬ 
eline, on the other hand, clings to the leather 
and lasts a considerable time. If the leather 
becomes dry it does not hold air well, and pump¬ 
ing to high pressure becomes impossible, while 
the labor of pumping even to low pressure is 
greatly, increased. 

Replacing Broken Ball. When replacing a 
broken ball in a ball bearing it is better to re¬ 
new the whole set, unless the new ball can be 
carefully gauged to be of the same size as the 
others. If this is not attended to, the new ball, 
having to bear more than its share of the 
weight, quickly succumbs. The greatest care 
should be taken, of course, to use grease free 
from grit, and to clean the balls and bearings 
before they are replaced. 

Cleaning Tops. Tops may be cleaned by us¬ 
ing gasoline, a little ivory soap and a brush. 
Sometimes, however, when cleaning with gaso¬ 
line the water-proofing quality of the materials 
may be destroyed. This can be restored by an 
application of paraffine. Dissolve the paraffine 
with gasoline and apply with a clean brush, the 
gasoline will carry the paraffine into the fabric 


The Automobile Handbook 


573 



■Ak) M 





































































574 


The Automobile Handbook 


and will evaporate, leaving the paraffine in the 
fabric. 

Useful Hints. At A, Fig. 270a, is shown a 
simple tool found to be universally useful for 
wedging off magneto driving pinions, and other 
small members fitted to coned shaft ends, with 
or without key retention. This can be easily 
made from a large file, or any piece of steel of 
sufficient dimensions, depending upon the work 
to which it would be applied. The opening in 
the fork need not be more than three-quarters 
inch for the average magneto, the tines about 
two inches long, and three-eighths inch wide and 
taper from nothing to about one-quarter inch 
at the thickest part. Two of these are needed 
and are placed back of the gear, the tapered 
portion of one piece resting on that of the 
other, as shown. To remove the gear the ends 
are driven in toward the centre at the same 
time. This exerts a. lifting effort, due to the 
wedge action of the tools immediately back of 
the pinion. The advantage of this method is 
thafiffhe shaft on which the gear is mounted is 
not subjected to any side strains, such as would 
result if attempts were made to drive off the 
gear by holding an S wrench back of the gear 
and driving against it with a hammer. When 
removing worn sprockets from the counter 
shaft in order to replace them with new ones, 
trouble may be experienced in loosening the 
nut especially if the rear wheels have been re¬ 
moved. In such cases the chain may be utilized 


The Automobile Handbook 


575 


to hold the sprocket in the manner shown at 
JB, Fig. 270a, by anchoring it to the axle with 
an S hook made of three-eighths inch cold rolled 
steel rod The sprocket will be firmly held and 
the nut removed without difficulty. 

Although some grades of rubber hose are bet¬ 
ter than others, unless properly cared for even 
the best will deteriorate rapidly. Among the 
factors which make for rapid wear are careless 
stowage and abuse. The hose is left on the 
wash stand, cars are run over it, and when it 
has served its purpose, it is thrown in a heap 
and oil and grease accumulations soon work 
havoc with the rubber walls. A good rule to 
follow is to have a place for everything and 
everything in its place. It is not unusual to 
see a coil of hose carefully hung upon a nail, 
as shown at C, each coil having a sharp 
“kink” in it, both top and bottom, as indicated. 
This sharp bend tends to break the fabric walls, 
and the hose soon leaks. The proper way of 
hanging a hose is to use five or six wooden pegs 
arranged around an arc of a circle, as shown. 
Under these .conditions the coils take a grad¬ 
ual curve, and do not assume a sharp angle as 
when but a single point of support is utilized. 
If the hose is one of some length a reel should 
be used. 

Often when fitting bushings and parts, and 
in general operations where reamers are used 
it is found that the tool will he just a trifle 
undersize, or that it is desirable to have the 


o/b 


The Automobile Handbook 


reamed hole just a little oversize. In such cases 
a simple expedient, as shown at D, Fig 270a, will 
be found valuable. A small sheet of brass, or 
zinc is rolled in such a manner that it will fit 
between two of the cutting edges of the reamer. 
If the reamer is inserted with the roll of metal 
in place it will be evident that the reamer will 
be forced a tritie from the centre of the bore 
and the cutting edges of the reamer opposite 
the inserted metal roll will remove the metal. 
Very fine cuts should be taken, and the metal 
roll placed between different cutting teeth each 
time that the tool is used. In tapping out nuts 
it is often desirable to have the thread a little 
deeper than the standard, or to have the nut a 
loose fit on the bolt, as is sometimes necsesary 
when trying to place a machine screw nut on a 
carnage bolt. In this case a similar roll of 
metal may be placed between the cutting edges 
of the tap, as shown at E, Fig. 270a. 

Solder. Silver solders are generally used for 
very fine work. They are very fusible, and 
non-corrosive. Hard spelter is used for steel 
and iron work, and soft spelter for brass work. 

When copper is soldered to iron or zinc, resin 
should be used, or if chloride of zinc is used for 
a flux, the joint should be washed afterwards 
to remove the acid. Un-annealed wires should 
be soldered at as low a temperature as possible. 
Solder is always an alloy of other metals. It 
must not only be more fusible than the metal, or 
metals to be joined, but it must have some chem- 


The Automobile Handbook 577 

ieal affinity for them. Different kinds of solder 
are therefore employed for different purposes. 
It is called either hard or soft, according to its 
fusing point. 

Solders and spelters for use with different 
metals, and their proportional parts by weight 
are 

Solder for: 

Electrician’s use—1—Tin, 1—Lead. 

Gold—24—Gold, 2—Silver, 1—Copper. 
Patinum—1—Copper, 3—Silver. 

Plumber’s—Hard—1—Lead, 2—Tin. Soft—- 
3—Lead, 1—Tin. 

Silver—Hard—1—Copper, 4—Silver. Soft— 
1—Brass, 2—Silver. 

Tin—Hard—2—Tin, 1—Lead. Soft—1—Tin, 
1—Lead. 

Spelter for: 

Fine brass work—8—Copper, 8—Zinc, 1—• 
Silver. 

Common brass—1—Copper, 1—Zinc. 

Cast iron—4—Copper, 3—Zinc. 

Steel—3—Copper, 1—Zinc. 

Wrought iron—2—Copper, 1—Zinc. 

Side-Slip of Motor-Cars. A wheel with a 

weight on it wdien rotating bites into fresh 

ground as it advances. If the wheel rotates more 

in proportion than it advances, from any cause, 

it thereby loosens the particles of dirt beneath 

it and loses adhesion with the ground immedi- 

atelv under the dirt. 

•/ 

The wheel can now slip sideways as easily 



578 


The Automobile Handbook 


as it can slip forwards, particularly when it lias 
the rounded section slightly flattened, which is 
the case with pneumatic tires. When traveling 
straight ahead, and with the motor out of gear, 
skidding does not usually occur. A slight turn 
given to the steering wheel checks the speed and 
introduces a side pressure on both front and 
rear wheels, due to the machine tending to con¬ 
tinue its path in a straight line. Generally this 
side pressure will not cause skidding. If, how¬ 
ever, the motor be suddenly thrown in gear, or 
the brakes suddenly applied, or, what amounts 
to the same, a large turn is given the steering 
wheel, the wheels find themselves either rotat¬ 
ing more than in proportion to their advance, or 
advancing more than in proportion to their ro¬ 
tation. This immediately causes a loss of ad¬ 
hesion, which, once established, causes the car 
to skid or side-slip. 

Spark—Regulation of. l T pon the proper use 
of the sparking device depends the economy of 
the motor, and in many cases the safety of the 
driver. On some cars the sparking point on the 
magneto is fixed, and the autoist controls the 
car by the throttle only. There are a number 
of cars in use which employ the battery in con¬ 
nection with separate coils or a single spark sys¬ 
tem, or a magneto on which the spark can be 
regulated hv the driver. When starting, the 
spark should be retarded in the case of battery 
ignition, to prevent backfiring, and slightly ad¬ 
vanced to a certain point, depending on the 


The Automobile Handbook 


579 


motor and magneto, in the case of magneto igni¬ 
tion. When it is desired to slow the motor 
down below the point obtained by throttling 
only, the spark is likewise retarded. In ordi¬ 
nary running, a position of the spark lever can 
be found which will give fair average results 
through a considerable range of speed without 
changing its position, and this position varies 
with each motor, and can be found by experi¬ 
ence. When a higher rate of speed is desired, 
the throttle is opened and the spark advanced 
gradually. If a grade is to be negotiated it 
should be “rushed” if possible, the throttle be¬ 
ing opened full and the spark well advanced 
until the motor begins to slow down and 
‘ ‘ knock, ’ ’ when the spark should be retarded to 
correct this. The autoist should always keep 
the spark as far advanced as possible, without 
causing the motor to knock. When accelerating, 
or retarding, the spark should follow the throt¬ 
tle, the latter always being operated first. 

Spark Plugs. The trouble with motors mis¬ 
firing, is generally due to dirty spark plugs. 
This is caused by using too much cylinder oil, 
which, when subjected to the intense heat in the 
cylinder, turns to carbon. This carbon depos¬ 
its on the insulated porcelain and the body of 
the plug, and instead of the current jumping 
from the point in the body to the point in the 
porcelain and making a spark, it follows the 
easiest path, which is the carbon, and does not 
make a spark at the plug points at all. When 


580 


The Automobile Handbook 


this occurs the motor will misfire. The first thing 
to do when a motor misfires is to test the spark 
plug. Turn the motor until the battery circuit 
is closed. Unscrew the spark plug from the mo¬ 
tor, then reconnect the wire to it just the same 
as it was before. Lay the metal part of the 
plug body on the flywheel or some other un- 



A—Platinum point. 

B—Thread. 

C—Plug body. 

D—Bushing. 

E—Insulated terminal. 


Fig. 271 

F—Porcelain bushing. 
G—Expansion spring. 
II—Asbestos washer. 
J—Lock nuts. 

K—Assembly nut. 


painted part of the motor, being careful that 
the metal part of the plug body only touches 
the motor and that the porcelain part is clear. 
If the spark jumps in short jerks between the 
inner end of the porcelain and the interior of 
the plug body it is sooted, and needs cleaning. 
































The Automobile Handbook 


581 


If it jumps at the points as it should do, the 
trouble is elsewhere; probably at the battery, 
loose connecting wires, or the vibrator of the 
coil is not properly adjusted. 



SPARK PLUGS 


Fig. 272 

To clean a spark plug properly use a 50 per 
cent solution of hydrochloric (muriatic) acid, 
washing the points of the plug with a tooth 
brush, occasionally dipping the plug into the 



SPARK PLUG 


Fig. 273 

acid. After cleaning the spark plug in this 
manner, rinse it in water. 

Spark Plugs—Construction of. Two spark 
plugs are shown in Figure 271, which, while dif¬ 
fering radically in their construction, effect the 




































582 


The Automobile Handbook 


same purpose, that of producing a spark or arc 
in the combustion chamber of the motor. The 
accompanying table and reference to Figure 
271, will fully explain the construction of the 
spark plugs. 

Cross-sections of four different forms of 
spark plugs are shown in Figure 272. All are 
constructed with a view to make the outside or 
extraneous path caused by sooting, as long as 



possible, so as to prevent if possible short-cir¬ 
cuiting of the plug from this cause. 

Figure 273 shows a form of spark plug in 
which two extra air-spaces are provided, one 
between the center rod or terminal and the 
porcelain bushing and the other between the 
porcelain bushing and the shell or body of the 
plug. 

The spark plug shown in Figure 274 has a 
closed chamber around, and over the center in¬ 
sulated rod or terminal; this chamber is a part 

















































The Automobile Handbook 


583 


of the body of the plug and forms the other ter¬ 
minal of the plug. It acts as a small combus¬ 
tion chamber, and streams of fire are supposed 
to be thrown from the small openings in the 
chamber, when the arc or spark occurs therein. 



SPARK PLUG 


Fig. 275 


An exterior view of a form of spark plug in 
general use is shown in Figure 275. 

Spark plugs of American manufacture are 
made with three different sizes of threads: One- 
half inch pipe-size, the actual outside diameter 
of which is .84 of an inch, with 14 threads Dei 1 

































584 


The Automobile Handbook 


inch. Three-quarters of an inch diameter, with 
18 threads per inch, and .7 of an inch diameter, 
with 17 threads per inch. The last named one 
is the French, or Metric standard thread. 

Spark Gap, Extra. An extra spark gap in 
the secondary circuit will cause a spark to jump 
across the points of a fouled plug because the 
intensity of the voltage of the current is re¬ 
duced to such an extent that the current will 
jump across the points in preference to the path 
of higher resistance formed by the carbon de¬ 
posit upon the insulation of the spark plug. As 
the spark plug and the spark gap are in series 
• with each other, it follows that v r ith a single 
gap—the spark plug alone—the tension of the 
secondary circuit is about 30,000 volts, while 
with two gaps the tension at each gap will be 
onlv about 15,000 volts. That this statement 
is true may be shown by an arc light circuit of 
500 volts, with five 100-volt lamps in series with 
each other in the circuit, and which have a po¬ 
tential of 100 volts each, and not 500 volts, as 
might be supposed. This explanation, there¬ 
fore, destrovs the claim that the use of the ex- 
tra gap intensifies the arc or spark at the points 
of the plug. The real advantage of the extra 
gap is that the reduction of the voltage, instead 
of its increase, reduces the tendency of the cur¬ 
rent to arc across the carbon deposit. 

The extra spark gap will only be found ef¬ 
fective so long as the carbon deposit upon the 
insulation of the spark plug is small, or mixed 


The Automobile Handbook 


585 


with oil, which increases the resistance of this 
path- The arcing will continue at the point of 
the plug until the carbon deposit is rich enough 
to form a path for the entire volume of the 
current, when the plug will cease sparking—- 
but the extra spark gap will continue to arc. 
One advantage of the extra spark gap is that it> 
provides a means of seeing whether the second¬ 
ary circuit is in working order without remov¬ 
ing the plug from the cylinder, and the device 
should be connected in the circuit by a two- 
point switch to enable it to be thrown in, and 
out of the secondary circuit. The use of the 
extra spark gap will never absolutely remove 
the necessity for keeping the insulation of the 
spark plug in good condition and free from soot 
or oil. As long as the batteries are strong 
enough to maintain the full voltage of the pri¬ 
mary circuit, just so long will the extra spark 
gap work successfully in the secondary circuit, 
and when the electromotive force of the batter¬ 
ies faHs below the normal point, it will be found 
necessary to cut out the extra spark gap, to 
maintain an efficient spark in the combustion 
chamber of the motor. 

Specific Gravity. In the absence of a proper 
instrument, the specific gravity of gasoline or 
any other liquid may be obtained as follows: 

Weigh a certain quantity of distilled water 
at 4 degrees Centigrade, or 39 1/3 degrees Fah¬ 
renheit. 


586 


The Automobile Handbook 


Weigh the same quantity of gasoline or other 
liquid under test. 

Divide the weight of the liquid by the weight 
of the water, and this will give, the required 
specific gravity of the liquid. 

The specific gravities of various liquids are 
as follows: 


Alcohol at 15° C. 0.704 

Acid, nitric. 1.217 

Acid, sulphuric . 1.841 

Ether at 15° C. 0.720 

Naphtha . 0.848 

Oil, linseed. 0.04 

Petroleum. 0.878 

Gasoline at 1.1° C.0.6S0 to 0.720 

Water, sea. at 4°. 1.026 

Water, pure, at 4°. 1.0 

Speed, Cyclic Variation of. The cyclic irreg¬ 
ularity of any reciprocating-piston motor is 
defined as the ratio of the difference between 
the maximum and minimum velocity in any one 
revolution to the mean velocity. The great 
difficulty in measuring this ratio is the contin¬ 
ual variation in the mean velocitv. One system 
of measurement uses a tuning-fork, which 
traces a wavy line on a smoked cylinder at¬ 
tached to the motor shaft. Another apparatus 
consists of a disc attached to the motor shaft, 

and a flywheel turning freely on the same axis. 
% 

The disc and flywheel are geared together bv a, 
planetary gearing, whose axis, perpendicular to 
that of the flywheel, carries a pencil point trac¬ 
ing on a rotating drum. The flywheel is turned 
through the planetary gearing, and takes up 
the mean speed of the motor. As it is too heavy 
to follow the cyclic variations in speed of the 












The Automobile Handbook 


587 


disc, these cause the axis of the planetary gear¬ 
ing to move backward and forward round the 
axis of the disc, and the pencil point therefore 
traces a periodic curve on the drum. This 
curve, however, does not give the difference in 
velocity, but the relative change in position of 
the disc and flywheel, and the maximum differ¬ 
ence in velocity must be calculated from the 
two steepest tangents to the curve. This appara¬ 
tus is troublesome in the calculation of results 
and is not sufficiently sensitive for small irregu¬ 
larities. An apparatus constructed on the prin¬ 
ciple of the Von Alteneck transmission dyna¬ 
mometer is also used for this purpose, a pulley 
attached to the motor shaft being connected by 
a belt to a flywheel, which takes up the mean 
velocity of the motor, the variations in velocity 
produce variations in the tension on the two 
sides of the belt, and an index is arranged to 
measure these. The elasticity of the belt ren¬ 
ders this apparatus unsuitable for any absolute 
measurements. Another device consists of a 
heavy cvlinder, mounted on an axis fixed to the 
motor shaft by ball-bearings; the friction in 
these causes it to take up the mean velocity. A 
frame fixed to the shaft embraces the cylinder, 
and carries a pencil point which is free to move 
along the cylinder. A string attached to the 
pencil passes over a pulley to a sleeve running 
free on the axis; if this be held still, the string 
winds up on it, and pulls the pencil along the 
cylinder. As the motion of the cylinder is uni- 


588 


The Automobile Handbook 


form, while the pencil follows the irregularities 
of the motor, the latter traces a curve, from 
which the cyclic irregularity can be reckoned. 
This apparatus was found to work well, hut 
was not sufficiently sensitive for small irregu¬ 
larities. 

The only method which has been found capa¬ 
ble of measuring a very small irregularity is to 
employ a small independently excited dynamo 
driven by the motor, and take its curve of volts 
by means of a Joubert contact-maker and po¬ 
tentiometer. As the volts are proportional to 
the speed, this gives also the curve of speed of 
the motor. If there be no irregularities in the 
dynamo voltage due to its construction, this 
method is capable of giving very accurate re¬ 
sults, but it is troublesome and unsuited for 
practical work. 

Speed of Gasoline Motors. In explosive mo¬ 
tors the products of combustion diminish in 
about the ratio of the increase of speed. The 
pressures and temperatures at admission and 
exhaust are variable, and depend on the speed 
and the mean temperature of the cylinder wall. 
The compression pressure decreases in propor¬ 
tion to the increase of speed, owing to the di¬ 
minished volume of mixture at, higher speeds. 
If it were not for this the power of a motor of 
given bore and stroke would go up in the same 
proportion as the speed. 

An automobile motor differs fundamentallv 
from the stationary form by reason of its being 


The Automobile Handbook 


589 



Fig. 276 
Speedometer 



590 


The Automobile Handbook, 


required to run at variable speeds. If the valves 
are well designed, nearly the full volume of 
gas should be taken in at higher speeds, and 
the compression will actually improve at higher 
speeds owing to the diminished time for leakage 
round the piston-rings. This tends to improve 
the fuel economy of the motor. 

Speedometer. Speedometers for automobile 
use are made for attachment to the dashboard, 
and are actuated by means of a flexible shaft 
and gear attachment to the wheel of the car. 

The driving gear consists of a large gear at¬ 
tached to the hub of the wheel, and a small gear 
carried by a ball-bearing shaft at the end of the 
flexible cable and supported on the steering 
knuckle by means of an attaching bracket. By 
a series of different gears the instruments mav 
be adapted to any standard wheel from 28 to 
40 inches in diameter. The change is made by 
simply removing a cotter pin and substituting a 
gear of a different diameter and number of 
teeth. 

The ball bearing shaft is provided with a 
swivel base, which permits the gears to separate, 
and dislodge any obstacle that may come be¬ 
tween the teeth, thereby preventing damage to 
the gears. The spring in the swivel base oper¬ 
ates automatically to bring the gears back into 
mesh. 

The flexible shaft consists of a woven steel 
wire cable enclosed in a strong brass casing. It 
is of proper length to permit of the attachment 


The Automobile Handbook 


591 


of the instrument to the driver’s side of the 
dashboard, and to connect with the gears on the 
front wheel of the car, with allowance for am¬ 
ple play at the gear end to prevent it receiving 
any strain through the swinging of the wheel 
in steering. 

No lubrication is required, as this is provided 
for when the instruments are assembled. The 
flexible shaft casing is partially filled with a 
composition of graphite and cosmoline, which 
works down and lubricates thq ball-bearing 
small gear shaft. 

Speed is indicated whenever the car is mov¬ 
ing; whether forward or backward. Distance 
is registered cumulatively whether the car goes 
forward, or backward. 

Springs. The length and number of leaves 
in the springs of motor cars of similar weight 
and power vary, and without any reason for so 
doing. The general use of pneumatic tires hides 
many imperfections in this respect as well as 
in others. Springs of insufficient strength are 
a source of great danger, and frequent exami¬ 
nation should be given to them. Springs are 
not necessarily of insufficient strength because 
they appear to be light. Short springs are not 
desirable, as they are more liable to break than 
a longer spring, the deflection per unit of 
length being greater. Stiffness in short springs 
is usually avoided by lightness, which is likely 
to lead to breakage, especially when the hole 


592 


The Automobile Handbook 


for the bolt through the center of the spring is 
made larger than necessary. 

Springs—Dimensions of. In calculating the 
dimensions and elastic limit of springs for mo¬ 
tor-car use, the elastic limit must be carefully 
considered with regard to the dead, and maxi¬ 
mum loads to be carried by the car. The dead 
load is the weight of the car when at rest. The 
maximum load is the greatest weight that can 
possibly be carried with good spring action. 
The springs to retain their elasticity should 
have their ultimate strength far beyond their 
maximum load capacity. 

The old practice of fixing a uniform curva¬ 
ture of the spring leaves frequently leads to 
breakages due to distortions set up at the 
spring perch. This tendency is now aborted by 
making the spring leaves in such a way that the 
curvature begins at points beyond the spring 
perch, so that the clamps when they are pulled 
into tight relation do not straighten out the 
plates. It is still the custom to use a leather 
pad on which to rest the springs, because 
thereby the coefficient of friction becomes that 
of leather, and creeping tendencies are as a con¬ 
sequence remote. There is also the question of 
the camber given to the respective spring plates. 
If the plates are all of the same thickness, they 
should all be curved to the same radius, for 
then the extreme fiber strain would be equal in 
all the plates for every alteration in camber in- 


The Auto mobile Handbook 


593 

cidental to the service they are placed to per¬ 
form. 

Springs — Testing and Material. The life of 
a spring is forecast by the maker thereof, al¬ 
most independently of the quality of the mate¬ 
rial. If the spring is limber, and it is so placed 
as to indicate spring play, just at the point of 
reversals of camber, the life will be shortened. 
The superior grades of materials will stand this 
abuse for a comparatively long time, but the 
dynamic life of steel, like the life of every other 
animated thing, is limited. Inferior materials, 
advantageously situated, might last far longer 
than the superior products working at a disad¬ 
vantage. The initial camber to give a spring, 
for a given static camber, is a problem for the 
springmaker. 

Fig. 277 shows three views of a given spring, 
under the conditions as follows: The spring 
under static load, indicating the static cam¬ 
ber; straightened out under load; in reverse 
camber, in a testing machine, to the limit before 
permanent set. 

rt is worth while to study these three condi¬ 
tions in relation to springs, because they have 
to do with the life of the spring in service, and 
the easy riding qualities of the car due to spring 
action. It might be said in general that the 
greater the difference between the initial and 
the static camber, the more pronounced will be 
the easy riding qualities, and it might be said 
as well that the greater the initial camber, and 


594 


The Automobile Handbook 


the greater the possible reverse camber, the bet¬ 
ter will be the life of the springs, especially if 
we take into account that the spring action in 
service will be limited between the two points, 
as represented by the initial camber on the one 
hand and the condition, which means that the 
spring leaves will no more than straighten out 
in actual service. If the service conditions are 
such as to eliminate any reversal of camber, 



Fig. 277 


then it may be said the factor of safety will 1m 
represented by the amount of the reverse cam¬ 
ber in a testing machine before permanent set. 

Springs—Care of. Springs should be exam- 
onally, and while often overlooked, 
this seemingly trifling matter has a direct bear¬ 
ing upon the smooth, easy running of the car. 
Owing to the fact that the springs are exposed 
to the weather, rust is very likelv to occur at 
















The Automobile Handbook 


595 


this point, and to this unsuspected corrosion is 
often due the occasional “squeak.” Although 
many cars are provided with some means for 
fabricating the friction surfaces, many cars are 
not so well provided for and when rust makes 
its appearance along the joints there is a cry¬ 
ing need for oil. This mav be conveniently 
applied by placing the jack between spring and 
frame, and slightly opening the leaves or plates. 



The toggles and links should also have a little 
oil occasionally and when about this work it is 
well to examine the nuts of the clips. These 
nuts are prone to work loose. 

The steering gear should always be given 
proper care and the levers, pins and joints 
should be kept free of dirt and well oiled. This 
is a very important matter, and as neglect may 
result in a bad accident, injurious to both driver 
and car, this important mechanism should be 
given frequent and critical examination. 





51)6 


The Automobile Handbook 


Sprockets. The circular instead of the linear 
pitch is often erroneously used in calculating 
the pitch diameter of a sprocket wheel. Refer¬ 
ence to Figure 278 will illustrate the difference 
between circular and linear pitch, and help to 
demonstrate the case more clearly. The view at 
the left of the drawing shows the circular pitch, 
and the view at the right the linear pitch of a 
gear or sprocket wheel respectively. If the cir¬ 
cular pitch of the gear be one inch and the gear 
has six teeth as shown, the pitch diameter will 
be 6 X 0.3183, which gives 1.91 inches as the 
pitch diameter. Let the linear pitch of the 
sprocket be also one inch, and with six teeth as 
before. In a sprocket having 6 teeth, the ra¬ 
dius is equal to the linear pitch, as the figure is 
composed of six equilateral triangles, and the 
pitch diameter of the sprocket wheel is conse¬ 
quently 2 inches. 

Sprockets, Dimensions of. Table 16 gives the 
pitch diameters of sprockets for roller chain of 
1 inch, l 1 /^ inch and 1 y 2 inch pitch, with 7 to 
28 teeth. The outside diameters may be found 
by adding the diameter of the roller to the pitch 
diameter of the sprocket. 

Sprocket Chain Lubrication. The best lubri¬ 
cant for sprocket chains is a constant puzzle. 
Tf oil is used it is absorbed by the dust which 
settles on the chain. If tallow or other animal 
grease is employed it is pushed away from the 
Fearing surfaces, and the latter get dry. The 
ideal lubricant would seem to be something be- 


The Automobile Handbook 


597 


TABLE 10. 

DIMENSIONS OF SPROCKETS FOR ROLLER CHAIN. 


Number of 
Teeth in 
Sprocket. 

1 Inch 
Pitch. 

144 Inch 
Pitch. 

lYz Inch 
Pitch. 

Pitch Dia. 

Pitch Dia. 

Pitch Dia. 

7 

2.31 

2.88 

3.46 

8 

2.61 

3.27 

3.92 

9 

2.02 

3.65 

4.38 

10 

3.24 

4.04 

4.85 

11 

3.54 

4.44 

5.33 

12 

3.S6 

4.83 

5.79 

13 

4.18 

5.22 

6.27 

14 

4.50 

5.62 

6.75 

15 

4.81 

6.01 

7 22 

16 

5.12 

6.41 

7.09 

18 

5.76 

6.41 

8.64 

20 

6.39 

7.99 

9.59 

*/»> 

7.03 

S.79 

10.55 

24 

7.66 

9.58 

11.49 

26 

8.31 

10.38 

12.44 

28 

8.95 

11.19 

13.42 


tween an oil and a grease, too thick to be drawn 
out* by absorption, yet soft enough and clinging 
enough to stay in the rollers. This mission is 
approximately fulfilled by a mineral grease, 
such as non-fluid oil, or Keystone grease, which 
are not affected by moderate changes of tem¬ 
perature, and have the clinging quality which 
animal greases lack. The makers of these 
greases, however, do not recommend heating 
them, and they cannot be introduced into the 
links and rollers of the chains, except by ren¬ 
dering them temporarily more fluid than they 
are desired to be in service. A very good lubri¬ 
cant for this purpose is made by dissolving Key¬ 
stone grease in gear case oil, in amounts suffi¬ 
cient to produce a viscous fluid at the boiling 

















508 


The Automobile Handbook 


point, which thickened when cold, and would 
just barely flow. A fairly liberal quantity of 
graphite was added, about half a cupful to three 
quarts of dope, and the chains after cleaning' 
were boiled for half an hour or longer in the 
mixture to enable it to penetrate thoroughly. 

Starting a Motor. The most important point 
about starting a gasoline motor is to ascertain 
if the cock in the supply pipe leading from the 
gasoline tank is open. Failure to do this has 
caused the display of more temper, profanity 
and anxiety than any other detail, except that 
of forgetting to close the switch before crank¬ 
ing the motor. Another point is to see that the 
tank has been previously filled with gasoline. 

Xext flush the carbureter to see if the gasoline 
flows from the tank, then give the motor one or 
two turns by means of the starting-crank and 
with the compression-release cock (if any) 
open. If a lnechanical feed, or splash lubrica¬ 
tion is used, there will be no necessity to look 
after the lubrication, but if a gravity oil feed 
is used, do not forget to turn on the oil before 
starting the motor. 

Never forget to retard the ignition before 
starting the motor. A back fire will result if 
this precaution is neglected, and a nasty blow, 
or even a broken wrist or arm may be the result. 
The proper way to avoid this trouble is to have 
the ignition lever spring-controlled so that the 
ignition is always retarded when the motor is 
not running. 


4 

The Automobile Handbook 599 

If the motor refuses to start, the trouble 
may be due to oil or grease on the spark plug 
points; this may be remedied without removing 
the plug, by disconnecting the secondary wire 
from the plug, and placing it near the terminal, 
so as to allow an external and visible spark to 
occur. Once the motor is started, the oil gets 
burned up by the heat, so that ignition will con¬ 
tinue after a permanent connection of the sec¬ 
ondary wire has been made. Generally it is 
necessary to stop the motor, or at least the 
spark, to facilitate re-connecting the wire with¬ 
out receiving a shock, but if the motor is hot it 
will re-start easily. This is merely a temporary 
adoption of the extra spark gap. 

Sometimes the motor will start readily, but 
dense smoke having a strong odor will issue 
from the muffler. This may be an indication 
that the mixture is too rich, although it is fre¬ 
quently due to an excess of lubricating oil in 
the cylinder. To correct the mixture, more air 
should be admitted to the carbureter. 

Failure of the motor to start is more often 
occasioned by too weak, than by too rich a mix¬ 
ture. The first thing to do, if regulating the 
air does not correct it, is to ascertain if the gas¬ 
oline pipe is free from obstruction. This pipe 
is not large, and is more or less crooked. A 
partial stoppage of the pipe will therefore re¬ 
sult in a too weak mixtuer. 

Water in the carbureter is not an infrequent 
cause of the motor failing to start. All gaso- 


The Automobile Handbook 


600 

line contains more or less water, which, being 
heavier than the gasoline, settles to the bottom 
of the supply tank, and finds its way to the 
carbureter. If the pet-cock at the bottom of 
the carbureter be opened, the water—which 
will have collected in the lowest part of the car¬ 
bureter—will pass out with the gasoline. 

Other causes of failure to start on the spark 
may be (1) leaky valves, (2) sticking of piston 
rings, (3) a leak around the cylinder or spark 
plug, (4) weak batteries. For valves or piston 
rings put two or three tablespoonsful of kero¬ 
sene into each cylinder, then close all compres¬ 
sion cocks and turn the motor over very slowly 
fifteen or twenty times, so that the compression 
will force the kerosene down past the piston 
rings. Then let the car stand for several 
hours. It might be necessary to repeat this op¬ 
eration for two or three nights. Then have the 
valves all carefully ground in, and see that when 
the valves are closed there exists between the 
puslirocls and valve stems a space equal to at 
least the thickness of an ordinarv visiting card. 
After securely replacing the cylinder and spark 
plugs, test them by applying a little oil or soapy 
water around the edges while the motor is be¬ 
ing turned over. Having secured good com¬ 
pression, overhaul the ignition system; see that 
the batteries are fully charged, coils properly 
adjusted and timing correct. A storage bat¬ 
tery, when fully charged, should show a voltage 
of 2.2 volts per cell, making 6.6 for a 6-volt 


The Automobile Handbook 


601 


battery. This may be used until the voltage 
drops to 5 volts, when it is advisable to have 
the battery re-charged. As to the timing of the 
spark, adjust it so that when the control lever 
is fully retarded, the spark will occur when 
the piston is about % or 1 inch down on the 
explosion stroke. Now, if the carbureter ad¬ 
justments are correct, the motor should start 
on compression. When starting this way is de¬ 
sired, the operator should turn off the current, 
then open the throttle wide. It is not necessary 
to race the motor, then switch off the current; 
the cylinders will get a better charge if just 
three or four slow revolutions are made after 
the ignition is cut off. 

Starting—Hard. It often happens that an 
engine after having been in operation for sev¬ 
eral miles and then stopped for a few minutes, 
cannot be started again until cooled by allow- 

i 

ing a quantity of cold water to pass through 
the radiator for several minutes. 

The trouble in many instances is due to the 
overheating of the cylinders to such a degree 
that the pistons are upon the point of seizing, 
in fact do seize for the time being, when the car 
is stopped with the water in the radiator at the 
boiling point. This would indicate insufficient 
water circulation, and the remedy is to put a 
larger driving, and a smaller driven gear on the 
pump, and thus increase its speed—this will 
cause the water to circulate at a higher speed, 
and thus carry away more heat, since the quan- 


602 


The Automobile Handbook 


tity of heat carried away varies directly with 
the amount of water circulated. 

In a set of gears of 6 pitch and 18 teeth, 
changing the driver to 21 teeth and the driven 
gear to 15 teeth will leave the center to center 
distance unchanged at 3 inches, and will in¬ 
crease the pump speed by 40 per cent. If this 
is not sufficient a later change to a driver of 24 
teeth, and a driven gear of 12 teeth will also 
leave the center to center distance unchanged, 
but will change the speed, increasing it 100 
per cent over the first arrangement and 43 per 
cent over the second method of gearing. 

Driving the pump faster will cure the trouble 
unless the pipes are clogged up. In fact, it 
would be well to go to the trouble of examin¬ 
ing these before making the other change, that 
is changing the speed of the pump by altering 
the gearing. 

Steam Automobiles. There are several ad¬ 
vantages possessed by steam motors as com¬ 
pared to explosive motors. For instance, speed 
variations are obtained without the shifting 
of gears, the speed being regulated by the throt¬ 
tle. The steam motor will start without crank¬ 
ing, and in operation it is noiseless. Also it is 
better for climbing hills. 

Principles of the Steam Machine. In all 
steam machines there must be a gasoline burner, 
a boiler, a steam engine, usually compound, a 
condenser, water pump, gasoline pump and a 
pilot lamp. 


The Automobile Handbook 


603 


The water in the boiler is converted into steam 
at a high pressure by the heat from the gaso¬ 
line burner. It is then conducted to the en¬ 
gine, where it performs its work in the steam 
cylinder, being used expansively whenever con¬ 
ditions permit. From the engine the steam is 
generally conducted into a condenser, which 
forms the front end of the car. After being 
partially condensed, the water flows into the 
water tank. There is a large fan behind the 
condenser, which aids the circulation of air 
between the tubes, thus increasing the efficiency 
of condensation. 

There is generally a feed water heater used, 
located in the exhaust pipe leading to the con¬ 
denser. The water, on its way from the pumps 
to the generator, passes through this heater 
and absorbs a certain amount of heat from the 
exhaust steam, after which it enters the boiler 
or generator. 

Fuel is supplied to the burner from a gasoline 
tank, which is generally equipped with a level 
indicator. The fuel is supplied to the burner 
under pressure, which is maintained by the air 
pump attached to the engine. The fuel passes 
through a vaporizer and then enters the burner, 
where it mixes with the air and burns. 

A pilot light is used for the two-fold function 
of heating the vaporizer, and lighting the 
burner, as fuel is generally only intermittently 
supplied to the burner, depending upon the 


604 


The Automobile Handbook 


steam pressure, which automatically regulates 
the fuel supply. 

The steam engine, which is used on steam 
automobiles, differs materially from the gasoline 
engine. A steam engine is double acting; that 
is, the steam acts on the piston during each 
stroke, so that there is always a pressure on one 
side of the piston which is available for work. 
For this reason the engine can never be stalled 
so long as there is pressure in the boiler. A 
steam auto engine is never made in four or six 
cylinders, like a gasoline engine, but is generally 
made with two cylinders, with cranks set at 90 
degrees with each other, so that there is always 
one crank which is in an effective turning posi¬ 
tion. 

There are two general types of steam engines 
in use on automobiles, two-cylinder simple en¬ 
gines, and two-cylinder compound engines. In 
the two-cylinder simple engine, such as used on 
Stanley steamers, each cylinder obtains its 
steam supply from the boiler, independent of 
each other. In the two-cylinder compound, 
such as used on the White, and Lane cars, there 
is what is called a high pressure cylinder, and 
the steam, after having been used in that cyl¬ 
inder, is used in the lower-pressure cylinder, 
which is always larger than the high-pressure 
cylinder, after which it is exhausted into the 
condenser. In the cases where simple engines 
are used, it is not usual to use a condenser for 
condensing the exhaust steam. 


The Automobile Handbook 


605 


Valve Gear. There are two types of valve 
gear in general use on steam automobile en¬ 
gines, which regulate the cut-off and allow the 
engine to reverse. These are the Stephenson 
link motion, and the Joy valve gear. Up until 
1909, the White steamer used the Stephenson 
link motion, but since that time the Joy valve 



use the Stephenson link, while the Stanley 
steamers use what might be classed as a direct 
valve motion, as it does not use the accepted 
Stephenson valve gear except when it is re¬ 
versed. The forward eccentric is held in for- 
Avarcl motion by spring pressure. For reversing 
a pedal button overcomes this pressure and 
throws into use the reverse eccentric. 








































(306 The Automobile Handbook 

Joy Valve Gear. This type of valve gear is 
now used on White steamers in place of the 
Stephenson link. The arrangements of the dif¬ 
ferent parts of the engine are shown in the ac¬ 
companying diagram, Fig. 279, in which P is 
the low-pressure steam piston shown at the top 
of the stroke, the high-pressure cylinder not 
appearing in the illustration. Steam is admit¬ 
ted to the upper, and also to the lower side of 
piston P by the piston valve V which has a re¬ 
ciprocating motion. The length of travel of 
valve V can be varied, and the quantity of steam 
admitted to the cylinder is thus regulated to 
suit the demand for power. The passage of the 
steam to the cylinder C is through ports S for 
the down stroke, and A for the up stroke, these 
ports being opened and closed alternately by 
valve V. This valve is what is termed inside 
admission, the steam entering ports S and A 
from between heads E and F of the valve, and 
exhausting around the outside of same. Valve 
V receives its motion from the connecting rod 
H, by means of the valve gear as follows: One 
end of link M hinges to H, and the other end to 
a bell crank B pivoted at point D which is sta¬ 
tionary. A link N hinges to link M, at one end, 
Avhile its opposite end carries a roller R running 
in a guide G. To link N near its outer end is 
connected the rod K for operating the valve. 
The length of travel of valve V is varied by 
tilting the guide G. With this guide tilted so 
that its outer end is lowered, giving it a hori- 


The Automobile Handbook 


607 


zontal position, there would be a minimum 
valve travel, and conversely if the guide be 
brought to a, greater tilt the result will be a 
greater valve travel. 

Reversal of the motor is also accomplished by 
tilting guide G. A line diagram, Fig. 280, 
shows the action of the Joy valve gear. The 
heavy lines show the system in one position, and 
the dotted lines in another position. The lower 
circle shows the path of the crank pin W. The 
ellipse immediately above it shows the path of 
point X, which is the point where link M is at¬ 
tached to the connecting rod H. The flattened 
ellipse to the right is the path of point Y, the 
connection of link N, and having a direct bear¬ 
ing on the movement of the valve. The flat 
oval at the left shows the path of travel of 
point Z which is the lower end of the valve 
connecting rod. This oval gives a definite idea 
as to the movement of the valve. According as 
the guide is tilted, or lowered to give different 
degrees of cut off, this ellipse will tilt, or reach 
the horizontal. The heavy lines show the rela¬ 
tive positions of all parts, when the piston is at 
its highest point as shown in Fig. 279, and the 
dotted lines indicate a point 90 degrees in ad¬ 
vance of this. In these engines the low pres¬ 
sure valve is 2 V 2 inches in diameter, and the 
hi^li pressure valve is 1*4 inches in diameter. 
Each valve is given 1/32 inch lead, and the 
maximum travel is l 1 /^ inch. 

The Toledo Steam Motor. Fig. 281 is a 


608 


The Automobile Handbook 



It has two vertical cylinders, double acting, 
and high pressure. The valves are of the pis¬ 
ton type as shown. The cylinder bore is 3 
inches, length of stroke 4 inches. The valves 
are operated by the Stephenson link valve gear. 


semi-sectional view of the Toledo steam motor. 
It is pivoted to the car body by a ball joint at 
the top, and is also held in position by a dis¬ 
tance rod passing to the back axle. 


rf 

Fig. 281 

Toledo Steam Motor 





The Automobile Handbook 


609 


The crank chambers entirely enclose the con¬ 
necting lods and cranks, the pins being’ lubri¬ 
cated by the splash system. The cylinders are 
lubi mated automatically from a steam-pressure 
tank of a capacity sufficient for 150 miles. The 
cross-heads for the two cylinders are connected 





Fig. 282 
Toledo Boiler 


with the plungers of two pumps fitted at the 
sides of the motor and enclosed in dust-proof 
casings. One pump is for the boiler feed water, 
and the other maintains an air pressure in the 
fuel tank. Relief cocks in the cylinders allow 
any condensed water to escape at starting. 


















































































610 


The Automobile Handbook 


The Duifders claim that this motor develops one 
horsepower per hour for each 24 pounds of 
steam consumption. 



Fig. 283 

Weston Steam [Motor 


Toledo Boiler. The Toledo water-tube 
boiler, Fig. 282, has one shell B within another, 
the chamber, A, between them forming an an¬ 
nular water space. Within the inner shell sev¬ 
eral lengths of weldless steel tube are wound 














The Automobile Handbook 


611 


spirally to form a central coil C; the ends of 
the tubes are fitted into the inner shell at top 
and bottom. The burner flame at D passes up 
between these tubes and causes rapid circula¬ 
tion, which prevents any deposit forming except 
at the bottom of the annular space. There are 



Weston Boiler 


small dams or scoops at the mouths of the tubes, 
where they open into the annular water space. 
The steam is taken from space A, superheated 
within the coil C, and passed to the motor 
through pipe E. The working pressure is from 
200 to 250 pounds per sq. in., and the boiler is 
tested to 600 pounds per sq. in. 







612 


The Automobile Handbook 


Weston Steam Motor. Fig. 283 shows a 6 
H. P. double-acting two-cylinder Weston motor 
with the customary link motion. The frames 
are of phosphor-bronze, and the majority of the 
bearings are of the ball type. 

The eccentrics and driving sprocket form a 
single drop forging, and the two cranks which 
fit into this piece at the ends are securely pinned 
in place. 



Weston Burner 


Weston Boiler. The Weston boiler, Fig. 
284, is an extremely simple, well made fire-tube 
boiler. The cylindrical shell, and tubes are of 
copper, the tubes being secured into steel end 
plates. Its heating surface is 45 sq. ft., and is 
tested to a cold water pressure of 600 pounds 
per sq. in. A safety valve blows off at a pres- 





The Automobile Handbook 


613 


sure of 225 pounds per sq. in. The burner, 
Fig-. 285, is of more particular interest. Two 
separate supply pipes lead to it, one feeding the 
pilot light, which heats the vaporizer tube, and 
the other leading through the vaporizer to the 
main burner. The driver regulates the fuel 
feed. For lighting the burner a small quantity 
of gasoline is allowed to How into the receptacle 
beneath the pilot lamp, which resembles an 
ordinary plumber's blow lamp. The gasoline 
is lighted, and as soon as the lamp is heated 
sufficiently, gasoline is fed to it at a constant 
rate. The flame of the pilot lamp plays upon 
the vaporizing tube which passes diagonally 
across, above the burner. Its and farthest from 
the pilot lamp is heated by the burner itself. A 
steel cable inside the tube acts as a distributing 
baffle for the main fuel feed, and increases the 
heating surface of the vaporizer. 

White Steam Generator. In this system the 
inter-relationship of water, gasoline and steam 
is both interesting and novel, and thus far, as 
demonstrated by daily use, has proven to be 
entirely satisfactory. The principles upon 
which it acts are: (a) the water carried in the 
tank must be delivered in proper quantities to 
the generator, where .it is flashed into steam; 

(b) this highly superheated steam must be gen¬ 
erated as fast as used, because no extra volume 
of it is carried as in the ordinary steam boiler; 

(c) the gasoline must be delivered in such quan¬ 
tity to the burner as to insure the maintenance 


614 


The Automobile Handbook 


of the proper degree of heat to generate suffi¬ 
cient steam. All this is accomplished by caus¬ 
ing the steam pressure to control the supply of 
water delivered to the generator, and the water 
pressure to control the gasoline supply to 
burner. The steam temperature also influences 
the water supply, as will be seen by the follow¬ 
ing description, as published in Motor Age. 

“The system is diagrammatically illustrated 
in Fig. 286. In the water system, the water 
must go from the water tank to the generator; 
it is drawn from the tank by two positively- 
driven pumps P, on the engine, through pipe 
PI. From each pump it follows the piping P2 
to the flow motor, whose workings will be con¬ 
sidered later; thence to the feed water heater 
which is simply a coil of pipe at the engine to 
heat the water before it goes through pipe P3 
to the generator. The pumps P are constantly 
working when the engine is running, always 
pumping the same amount of water per minute, 
at the same engine speed; but the reader will 
realize that sometimes more steam is needed 
than at others at the same engine speed, and 
consequently more water will be needed. The 
first device for regulating the flow of water is 
the water regulator into which the water flows 
by pipe P4. Its entrance to the regulator is 
governed by a valve, which only opens when 
the steam pressure gets above the 600-pound 
mark. This opening is accomplished by steam 
pressure through the pipe S3, acting on a dia- 


The Automobile Handbook 



615 


Diagram Illustrating System of Gasoline, Water and Steam in White Cars 


























































































































616 


The Automobile Handbook 


phragm which opens the valve, letting' the wa¬ 
ter enter the regulator, and escape through the 
pipe P5 back to the water tank, so that when 
there is 600 pounds pressure, which is the work¬ 
ing figure, the water delivered by the pumps P 
does not follow the course through pipe P2, to 
the generator, but is by-passed through pipes 
P4 and P5 to the water tank. This is the first 
feature of the water control. 

“With the water delivered to the generator 
gasoline must be delivered also in order to have 
heat to generate steam. The gasoline is carried 
under pressure in the tank at the rear of the 
chassis, and starts on its trip to the burner 
through pipe G, the first branch G1 goes to the 
pilot light which must be kept burning all the 
time the car is running. This pilot light is a 
small flame whose heat does not enter into 
changing the water into steam, but serves solely 
to light the gasoline vapor in the burner, as it 
must be realized the burner flame is out 1 min¬ 
ute, and on the next, according to the amount 
of steam required; the automatics of the system 
shut off and turn on the burner according to 
the demand, but the pilot light always burns to 
serve as the match for ignition. The gasoline, 
which goes to generate steam, follows pipe G2, 
into the pointed end of the flow motor, where its 
flow is regulated by a valve opened and closed 
according to the water pressure, and finally 
reaches the burner through the pipe G3. Some 
gasoline controlling valves are not shown in 


The Automobile Handbook 


617 


the diagram, the object of this diagram being 
merely to show the elements of the system. 

Having the water and gasoline at the genera¬ 
tor, steam is the product and its course to the 
engine is next in order. It follows the main 
pipe S, which, before reaching the engine, has 
an enlarged section Si which contains the cop- 



Fig. 2S7 

Water Regulator in White Cars 


per rod of the thermostat, and then reaches the 
engine through the continuation pipe S2. There 
is a branch S3 for conveying steam pressure to 
the water regulator. The pyrometer indicates 
the temperature of the steam. In brief, the ac¬ 
tion of the thermostat is to govern an additional 
supply of water to the generator. When the 
temperature of the steam gets too high, it means 



















































































618 


The Automobile Handbook 


more water is needed in the generator, and the 
thermostat delivers this extra water supply as 
follows: The higher temperature of the steam 
expands, or lengthens a rod, which through a 
rocker arm opens a valve, allowing water from 
the main supply pipe to flow through the pipe T 
and thence through pipe T1 into the flow motor. 
As soon as the steam temperature drops to nor- 



Fig. 288 

Thermostat in White Cars, for Regulating Water 


mal, the thermostat, through the copper rod, au¬ 
tomatically shuts off this water supply. There 
is a further control on the water by the flow 
motor, which, at a certain time, by-passes 
through the pipe W, water to the tank. The 
exact operation and construction of the water 
regulator, the thermostat, and the flow motor 
follow: 





























































The Automobile Handbook 


619 


The water regulator. Fig. 287, has as its most 
essential feature, a triple diaphragm D against 
one side of which the steam from the engine 
bears through the pipe S3. On the other side of 
the diaphragm is a metal member H adjustably 
secured to the shaft B, and which member at its 
opposite end bears up against the lever L, the 
lower end of which contacts with the stem of 
the valve Y. This valve Y regulates the water 
entrance P4 from the pumps, so that when the 
valve opens water enters and escapes by way 
of pipe P5 to the water tank. The coil spring 
S normally holds the piece H against the dia¬ 
phragm so that the valve V closes. However, 
when the steam pressure through S3 exceeds a 
certain figure, the diaphragm is forced to the 
right compressing the spring S and opening the 
valve Y, allowing the water to flow as men¬ 
tioned, the water, as illustrated in Fig. 286, be¬ 
ing by-passed to the water tank. 

The construction of the flow motor and its 
operation is more intricate but equally auto¬ 
matic. It consists of three parts, Fig. 289: 
The right section W in which the water control 
is adjusted; the small end portion G at the left 
which controls the gasoline flow to the burner; 
and the connective portion C. Water enters 
direct from the pumps through the port WE, 
and escapes through the latter opening WD, to 
the feed water heater. Its control of the water 
is by means of the piston P which, when moved 
leftward by water pressure, uncovers groove G, 


620 


The Automobile Handbook 













































































The Automobile Handbook 


621 


thus allowing the water to pass it and escape 
through the connections WD. This piston P is 
in rigid collection with the gasoline controlling 
valve GV, in the left compartment of the flow 
motor, so that valve GV also moves leftward, 
permitting gasoline which enters from the gaso¬ 
line tank through the opening GE to escape to 
the burner through another opening GD. The 
faster the engine runs the faster the pumps 
pump water, and the greater the water pres¬ 
sure against piston P the further will it be 
moved leftward against the spring S, the more 
water will pass it, and, proportionately, the 
more gasoline will go to the burner. When pis¬ 
ton P has traveled leftward a certain distance 
it contacts with the end H, which is on thp stem 
of the valve WV, and a further leftward move¬ 
ment of piston P opens the w T ater valve, which 
allows the water to escape through opening 
WD1, and thence to the -water tank. This pre¬ 
cautionary valve opens only when too much 
water is being pumped, and allows a portion to 
flow back to the tank. The entrance WEI is 
for water admitted from the thermostat control. 

The operation of the thermostat is shown 
in Fig. 288. Steam enters through SE from the 
generator and departs through opening SD to 
the engine. In its passage it contacts with a 
copper rod T anchored rigidly at one end E in 
the casing, and at the end El bearing upon a 
lever L which bears upon a collar on the valve 
stem VS. The high temperature of the steam 


622 


The Automobile Handbook 


lengthens rod T which, through lever L lifts 
valve Y from its seat, and allows water from 
the pumps to enter AYE and escape through 



Fig. 289a 


AVD to the flow motor. The valve A" begins 
opening at a temperature of 450 degrees Centi¬ 
grade. 







The Automobile Handbook 


623 


The connection P is with a pyrometer which 
shows the temperature of the steam on the 
footboard of the car. The accuracy of the py- 



Fig 289b 


rometer can be checked up by inserting a ther¬ 
mometer in the steam line at X. Thus do the 
water, gasoline and steam assist each other in 











624 


The Automobile Handbook 


this steam system. If the steam pressure gets 
too high it acts through the water regulator, 
and a portion of the water is thereby sent back 
to the tank instead of going to the generator 



to be made into more steam. The thermostat. 
when the steam gets too hot, opens a valve and 
allows more water to reach the generator 
through the flow motor, thus reducing • the 
steam' temperature; and the flow motor lets 
























The Automobile Handbook 



gasoline go to the burner in proportion to the 
water sent to the generator, and if too much 
water is pumped, returns a portion of it direct 
to the water tank. 

Steering Gear—Principles of. In steering 
gears the generally accepted principle is that 
known as the Ackermann-Jeantaud, which was 
invented in 1878 and is a modification of the 



Fig. 291 

Designing Steering Knuckle Arms 


original Ackermann principle. In the Acker¬ 
mann-Jeantaud system the steering knuckle 
arms OL and 01 LI, when produced, meet in the 
plane of the rear axle or in this plane produced 
as shown by illustration, Fig. 290. The reader 
will appreciate that when the tie-rod L L is in 
rear of the front axle, the steering knuckle 
arms OL and OIL converge, as illustrated, but 
should the tie-rod be in front of the axle, these 















626 


The Automobile Handbook 


arms diverge. Strictly speaking, the points A 
and AI, which are supposed to be in the axle 
plane, are not so, and the axle line A, AI, is a 



tangent to the curve in which the points of con- 
wugence will fall in a complete sweep of the 
steering wheels from axle to axle. 




The Automobile Handbook 


627 


Several makers have, however, discontinued 
the design of steering knuckles on this princi¬ 
ple, preferring to design them as illustrated in 
Fig. 291, in which the produced axis of the 
front wheels, A and B, intersect the axis of the 
rear wheel at a given point 0. With this con¬ 
dition fulfilled, the vehicle will travel around O 
as an imaginary center. Enthusiasts of this 
method of construction agree that the Acker- 
mann-Jeantaud principle is sufficiently accu¬ 
rate for angles of not more than 30 degrees, but 
for angles varying from 30 to 45 they claim less 
wear on their tires by the latter construction. 
The exact arm for the angles in a steering gear 
of this nature will depend largely on the wheel¬ 
base of the car as well as the difference between 
the steering pivots A and B. 

Steering Gear—Types of. Fig. 292 shows a 
sectional view of the nut and segment type of 
steering gear, in which there is a worm D on the 
steering column that engages with the nut E. 
On the front or gear face of the nut is a rack F 
which meshes with the sector G, so that as the 
steering wheel is turned right or left the nut is 
raised or lowered and the requisite movement 
imparted to the radius rod H. In certain screw 
and nut steering gears the sector is not required, 
the construction being a screw on the steering 
column on which works the internally threaded 
nut, and on either side of this nut are trunnions 
wifh links which connect with the axis carrying 
the radius arm. 


628 


The Automobile Handbook 


Steering Gear—Lost Motion in. If the gear 
is of the worm and sector type it may be that 
these two elements are not held in the proper 
relation to each other. Fig. 293 shows a dia¬ 
gram of this type of gear, and illustrates plainly 
the point where lost motion will be of the great¬ 
est detriment. When the wheel is turned, if 
there is the slightest end play, the wheel shaft 



will respond, but the geared sector will not, 
until all the end play is taken up, and as 
strains come on from the road wheels, the sec¬ 
tor will rotate to and fro, causing the shaft of 
the steering wheel to reciprocate and thus al¬ 
low the road wheels to wobble. To overcome 
tins it is necessary to replace the thrust washer, 
if there be one, and if necessary, introduce a 









The Automobile Handbook 


629 


” washer, made of phosphor bronze, of suitable 
thickness to take up all the end play of the 
steering wheel shaft. 

Some lost motion will follow if the worm is 
not set on the pitch line, in its proper relation 
to the sector; this will be true if the bushings 
are worn, and when a new thrust washer is 
made and fitted into place, if the lost motion is 
still greater than is desired, the only thing re¬ 
maining is to replace the bearing brasses. When 
the gear is dissembled it will be possible to di¬ 
mension the same, and determine by measure¬ 
ment if there is any great amount of journal 
wear, thus rendering the task less troublesome, 
since the brasses may be replaced without wait¬ 
ing to determine the remaining lost motion 
through actual trial. 

As a rule, it will be found that the lost motion 
is due to end play, just as the illustration shows, 
and not tb worn-out journal brasses on which 
the wear is far less than it is in thrust. If the 
gear is irreversible, or nearly so, as it is in many 
automobiles, a little lost motion is to be ex¬ 
pected owing to the smallness of the angle of 
the worm, which can only be irreversible if the 
angle is such that a little lost motion will be 
present and unavoidable. 

Care of Steering Gear. The steering gear 
is a very important part of the car, and, as the 
safety of the occupants may be endangered by 
any binding, the autoist should give it even 
more careful attention than the other parts. 


630 


The Automobile Handbook 



Fig. 293a 

Worm and Sector of Steering Mechanism 


The gear should be taken down, given a thor 
ough cleaning and examined for possible wear 






The Automobile Handbook 


631 


In case the steering action is stiff and the wheel 
turns hard, the ball joint may be out of adjust¬ 
ment due to wear; the steering link may be 
bent, or the cause may be insufficient lubrica¬ 
tion. If there is any considerable amount of 
backlash, the cause may be looked for in the 
joints of the levers, in the swivel pin, or in 
loose bearings. 

Stopping a Motor. After the run is finished, 
and the car is run -into the garage, the first 
work should be to shut off the battery switch 
and remove the plug. 

Close all oil cups or lubricators. 

Shut off gasoline if there is no float in the 
carbureter. 

In the winter, and if the car will be in a cold 
place, drain off the water from the circulating 
system. 

Wipe off the motor, and see that it is ready 
for the next run. 

When cleaning the motor examine all bolts 
and nuts, and all points needing adjustment. 

Note the condition of the journals and bear¬ 
ings, if they are hot, ascertain the cause of 
heating. 

Supplies Necessary on a Car. The following 
supplies will be found very useful, especially on 
a long trip: Asbestos, bolts and nuts, copper 
wire, emery cloth, emery powder, funnel, gaso¬ 
line (extra can), gaskets, iron wire, machine 
screws, rope (small, strong), rubber pail, sticky 
tape, washers. 


632 


The Automobile Handbook 


Suspension — Three Point. Where a three- 
point suspension is employed, as shown at A, B 
and C, Fig. 294, no amount of frame distortion 
will put any stress upon the power plant, or on 
individual members thereof, and, because of the 
unit construction, all parts will remain in ab¬ 
solute alignment. The advantages of the unit 
power plant construction are becoming better 
appreciated, and when this construction is not 



Fig. 294 

Three-point Suspension 


used the frame members must be proportioned 
to resist all stresses which might produce dis¬ 
tortion, and loss of alignment is prevented by 
stiffening of the frame. 

If an automobile were designed to run upon 
a perfectly smooth and unyielding surface, such 
as is presented by the rails of an efficiently 
maintained railway road bed, there would be 
no necessity for guarding against lack of align¬ 
ment. 



































The Automobile Handbook 


633 


But as it is compelled to travel roads that 
represent the furthest possible remove from 
this ideal, the importance of saving power that 
would otherwise be wasted in this manner, and 
of preventing these racking stresses from reach¬ 
ing the parts themselves, will be fully appreci¬ 
ated. When the motor is shoved upward 
through the action of the car in mounting an 
obstruction with its forward wheels, and at the 
same time the rear wheels are either dropping 
into a depression or mounting another obstruc¬ 
tion of a different height, there are heavy 
stresses tending to twist the frame in several 
different directions at once. The independent 
and rigidly mounted members assume all sorts 
of angles to one another. The motor imposes an 
additional burden on the clutch by dragging it 
out of line with the gear-set, and the clutch itself 
adds great!v to the load the transmission shafts 
must carry by tending to pull the gear-box into 
its own distorted plane. Instead of working 
harmoniously as a properly supported three- 
part unit, each adds to the burdens of the oth¬ 
ers, resulting in a constant need for expensive 
repairs. 

It will thus be apparent that it is not alone 
necessary to combine the essentials of the motor 
and transmission in the Unit Power-Plant, but 
that this rigid unit must be so carried that none 
of the twisting stresses can be transmitted to it 
by the frame. Assume a rigid rectangle of steel, 
to which a smaller rectangle of the same mate- 


634 


The Automobile Handbook 


rial is solidly fastened between, and parallel to 
the long sides of the larger member, and we 
have the usual frame, and subframe construc¬ 
tion. Twist the larger rectangle out of the hor¬ 
izontal plane, as is done by the rough road, and 
the smaller one will assume a correspondingly 
distorted angle. Take the large rectangle 
again, and instead of placing the small one in¬ 
side it, divide it into three rectangles by rivet¬ 
ing transverse members across the forward half. 
Result, the usual type of frame construction in 
which each essential is directly mounted on 
cross pieces forming part of the main frame it¬ 
self. Twist the latter, as before, and the ef¬ 
fect is exactly the same—no two members can 
remain in the same plane or conserve the same 
relation to the others. 

Instead of employing a second and parallel 
rectangle, or of dividing the larger into two or 
three sections, make the second frame triangu¬ 
lar, with its base supported on the main frame 
forward, and its apex flexibly hung on the cen¬ 
ter of a transverse member at the rear. Re¬ 
gardless of how the main frame, or rectangle, 
may be twisted, it does not impart the stresses 
of its distortion to the triangle, which, due to its 
flexible mounting, is free to maintain its own 
plane. This in effect is the principle of the 
Stevens-Duryea three point suspension illus¬ 
trated in Fig. 294a. The unit power plant con¬ 
stitutes the triangle previously referred to, and 
it is supported forward by means of two sub- 



Ci 

OJ 


eS • 

O 

s’cic 

£ a 

o; 













636 


The Automobile Handbook 


stantial aluminum alloy arms cast integral with 
the crank case, and at the rear on a special sup¬ 
port fixed on a transverse member designed to 
carry it. Fig. 294a also illustrates the accessi¬ 
bility of this system. When it becomes neces¬ 
sary to repair certain parts not easy of access 
while the power unit is suspended on the chas¬ 
sis, there is no need of laboriously lining its 
various parts up on the chassis, the entire unit, 
comprising the motor, clutch and gear-set, may 
be hoisted out of the car merely by uncoupling 
the forward universal of the propeller shaft and 
removing a few bolts. The entire operation 
consumes only a few minutes. 

Tachometer. A tachometer is an instrument 
for indicating the number of revolutions made 
by a machine in a unit of time—usually one 
minute. 

Tanks—Capacity of Cylindrical. To ascer¬ 
tain the capacity in gallons of a cylindrical 
tank of given length, multiply the area of the 
cross-section of the tank in square inches by 
the length of the tank in inches, and divide 
by 231. 

Tanks—Gasoline and Water. Do not put the 

water in the gasoline tank by mistake, as many* 
a new beginner has done. Always use a wire 
gauze-lined funnel. Although the drain of 
most tanks is usually a cock, the inlet is more 
often a screwed cap; this cap gets lost, and is 
often replaced by a cork. Tf this is done in the 
case of the gasoline tank, the results from pow- 


The Automobile Handbook 


637 


dered cork getting 1 into the carbureter and 
jmall pipes, is sure sometime to give rise to al¬ 
most endless trouble. 

Always till or measure the contents of the 
tanks before starting. When filling the water 
tank after it has been emptied, do so with the 
drain-cock open for the first few minutes so as 
to force out any air bubbles which might get 
into the pump, or in a bend in the pipes, and 




put a stop to the water circulation. This is 
known as an air-lock. 

In case that there may be difficulty in ascer¬ 
taining the level of the gasoline in the tank, 
gauge-cocks may be fitted in the side or end of 
the gasoline tank. Fig. 295 shows a form of 
gauge-cock suitable for this purpose. 

To determine the exact quantity of water in 
the tank, a gauge-glass as shown in Fig. 296 is 
well suited, as the fluid level mav be seen at a 

















6 38 


The Automobile Handbook 


glance. In case of accidental breaking of the 
glass, the cocks at the top and bottom of the 
gauge may be closed. 

Tap-Drills. See Table 17. 

TABLE 17. 


DIMENSIONS OE TAP-DRILLS FOR STANDARD V-THKBADS, FROM 

% TO 1 % INCHES. i 


Diameter 
of Screw. 

Number 
of threads 
per inch 

Diameter 
at bottom 
of thread 

Nearest 
drill for 

full 

thread. 

Correct 

size of tap 
drill. 

1-4 

20 

.163 

11-64 

3-16 

5-16 

18 

.216 

7-32 

1-4 

3-8 

16 

.267 

1 7-64 

7-32 

7-16 

14 

.314 

5-16 

23-64 

1-2 

12 

.3.76 

23-64 

13-32 

9-16 

12 

.418 

27-64 

31-64 

r>-s 

11 

.468 

15-32 

35-64 

3-4 

10 

.577 

37-64 

43-64 

7-8 

9 

.683 

11-16 

25-32 

1 

8 

.784 

25-32 

29-32 

1 1-8 

7 

.878 

7-8 

1 1-32 

1 1-4 

7 

1.003 

1 

1 5-32 


Testing Ignition Batteries. Get a 4 or 6-volt 

one-ampere incandescent lamp, and after cut¬ 
ting the battery out of the charging circuit, put 
the lamp in the battery circuit, for a few sec¬ 
onds only. If the battery is fully charged the 
lamp will give out a brilliant light. On no ac¬ 
count use an ammeter to test a storage battery. 
It will injure the battery if kept in the circuit 
long enough to get an accurate reading. 

Tires. A single-tube tire differs from a 
double-tube tire in the fact that the inner or 
air-tube is vulcanized to the outer tube. In a 
double-tube tire they are separately attached to 















The Automobile Handbook 


639 


the rim of the wheel, and are not in contact ex¬ 
cept when the inner tube is inflated. A punc¬ 
ture through the tread of a single-tube tire may 
be repaired by the use of rivet-shaped rubber 



Fig. 297 

patches, which are inserted in the puncture and 
secured in place with cement. With a double- 
tube tire, the casing must be removed from the 
rim of the wheel, and suitably sized patches are 



Fig. 298 

then cemented upon the inner tube according 
to the nature of the puncture. When a punc¬ 
ture occurs on the road, the double-tube tire 
may be repaired in a similar manner to the sin- 































6<f0 


The Automobile Handbook 


gle-tube, and when the tire is inflated, the air 
is retained by the inner tube, and prevented 
from leaking through the minute openings in 
the rubber and fabric of the casing. 

Fig. 297 shows cross-sections of single and 
double-tube automobile tires. 

The lower view in Fig. 298 shows a 
form of single-tube tire composed of a 
number of strands of thread running lon- 



299 

C 


gitudinally on the tube, and wound spirally 
with other threads which hold the longitudinal 
threads securely under inflation. The spiral 
windings are then pushed along the length of 
the tube, so as to reduce the distance between 
the windings from one-quarter of an inch to less 
than one-eighth of an inch, with the result that 
the intermediate sections of the longitudinal 
threads are pushed up into a series of loops, 
thus forming stronger attachments for the fab- 







The Automobile Handbook 


641 


ric, when lield in the rubber wall built up over 
these layers of threads. 

The upper view in Fig. 298 shows a method 



of strengthening the fabric of a tire against 
any cause that would tend to burst or tear 



open 1 lie walls, and is a series of plies or layers 
of thread wound on in diagonally opposite di¬ 
rections, each layer being of a more open con- 










042 


The Automobile Handbook 


struction than the last, the closest winding be¬ 
ing on the inner layer of the tire. 

A short section of an automobile tire with a 
tread having circular projections is shown in 
Fig. 299. It is said to increase the tractive or 
adhesive properties of the tire, and also to re¬ 
duce the danger of skidding, or side-slip to a 
minimum. 



Tire Repairs. A method of repairing a punc¬ 
ture in a single-tube tire by means of rivet- 
shaped plugs or patches is shown in Figs. 300 
and 301. Fig. 300 shows the manner of making 
the repair and Fig. 301 the placing of a strap or 
bandage of sticky tape around the tire and the 
rim of the wheel. The bandage is usually left 
on until it wears out. 

The manner of removing the casing of g, 
double-tube tire of the clincher type, to make 










The Automobile Handbook 


643 


a repair to the inner tube, is clearly shown in 
Fig. 302. 

Tire Pump. The proper unguent for the 
cupped leather washer of the tire pump piston 
is vaseline. Oil is too thin, and it tends to work 
into the rubber hose, and even into the tire it¬ 
self if too much is used. Vaseline, on the other 
hand, clings to the leather and lasts a consid¬ 
erable time. If the leather becomes dry it does 
not hold air well, and pumping to high-pres¬ 
sure becomes impossible, while the labor of 
pumping even to low pressure is greatly in¬ 
creased. 

Tonneau. The name or term used in connec- 
tion with the rear seats of a motor car. Liter¬ 
ally the word means a round tank or water 

«/ 

barrel. 

Tools Necessary on a Car. The following 
tools will not only be found useful but in 
many cases absolutely necessary on a car: Air 
pump, cold chisel, densimeter, files, hammer, 
jack, key puller, knife, monkey wrench, oil can, 
pliers, scissors, screw-driver, spanners, tire re¬ 
movers, tire-repair-kit. 

Touring Car. A car with non-removable rear 
seats and a carrying capacity of 5 to 6 persons, 
with from 16 to 24 horsepower, is known as a 
touring car. Such a car generally has a run¬ 
ning radius of 50 to io miles on one charge of 
gasoline and water. 

Touring Sundries. Extra parts and supplies 


644 


The Automobile Handbook 


necessary for use when on an extended tour 
*/ 

are as follows: 

Extra parts: C'liain links, batteries, inner 
tubes, insulated wire, packing, spark plugs, 
valves, valve springs. 

Supplies: Acetylene (carbide of calcium), 
cylinder oil, goggles, lap robe, lamp oil, lubri¬ 
cating oil, storm apron, tire bandage, waste, 
whiskey (for emergency use only). 

Torsion Rod. When the manner in which 
the power is transmitted from the change-speed 
gear to the rear axle on the shaft-driven car is 
considered, it will be apparent that the turning 
of the shaft imposes a twisting strain on the 
whole rear end of the car, and that if it were not 
for the frame, and the weight of the car on the 
ground, there would be a tendency to revolve 
the rear of the chassis around the shaft, rather 
than to turn the wheels. But it would be bad 
practice to permit this strain to fall on the frame 
and hence the office of the torsion rod, which is 
designed to prevent its reaching that member. 
On cars that are not provided with independent 
torsion rods, it will be found that the housing 
of the propeller shaft has been made corre¬ 
spondingly stronger, and that its supoprt has 
been designed to enable it to act in this double 
capacity. This represents a simplification of 
design that will be found on quite a number of 
cars, as it eliminates a part exposed to mud and 
dirt. 

Traction of Driving Wheels. A horse which 


The Automobile Handbook 


645 


exerts a pull of about 375 pounds continuously 
for an hour and goes a distance of one mile in 
an hour is working at the rate of one horse¬ 
power. If for any reason the horse is unable to 
exert as much as 375 pounds pull when going 
at the rate of one mile per hour, he is thereby 
prevented from working at the rate of one 
horsepower. 

The same rule applies to a motor car. When 
the road is not slippery there may occur a con¬ 
dition which does not appear with horse trac¬ 
tion ; that the tires fail to adhere to the ground 
owing to insufficient weight on the driving 
wheels. In such a case it is impossible for the 
motor-car to exert a push of 375 pounds with¬ 
out skidding the wheels, and thus it would be 
impossible for it to work at the rate of one 
horsepower. With underpowered motor-cars 
this difficulty does not occur, but to develop 10 
horsepower at the rims of the driving wheels 
while covering the ground at the rate of one 
mile per hour, the car must exert a push on the 
road of 3,750 pounds. This is, on touring cars 
of ordinary weight, impossible, because the 
weight on the driving wheels is invariably less 
than 3,750 pounds, while the adhesion with the 
road is only a fraction of the weight on the rear 
wheels. As the speed rises, however, the push 
necessary for the development of 10 horsepower 
goes down until at 10 miles per hour a push of 
375 pounds means 10 horsepower. 

Thus a 40 horsepower car, if it could start 


646 


The Automobile Handbook 


work with the activity of forty horses, would, 
while it was moving at one mile per hour, exert 
no less a push than 40 x 375, which is equal to 
15,700 pounds. This tremendous push is ren¬ 
dered impossible by the fact that the wheels of 
a car weighing 2,000 pounds only grip the 
ground enough to exert about 750 pounds push. 
Beyond this point they will skid. 

This shows that a high-powered car, when the 
car is moving slowly, cannot develop its full 
power unless the road wheels are capable of ad¬ 
hering to the ground sufficiently to transmit 
this power. As a rule only about 0.6 of the 
weight of the car is on the driving wheels, and 
of that only 0.625 is available for the adhesion 
(owing to the coefficient of friction between 
rubber and road being 0.625). So a 10 horse¬ 
power car weighing 2,000 pounds cannot exert 
its full power when the car is starting, nor until 
it is traveling at 5 miles per hour. 

It would be wrong to contend that on all 
cars having the weight distributed as at pres¬ 
ent, a 60 horsepower motor is useless, but it is 
needless to say that the output of such a motor 
is not availabe at starting or at any speed 
under 30 miles per hour, although the whole 
power is more needed then than at any other 
time. The remedy which suggests itself is by 
using all the adhesion of the car, that is, to 
drive with all four wheels. 

Transmission of Power—Efficiency of. The 
efficiency of various forms of drives between 


The Automobile Handbook 


r 


647 

the motor and the driving wheels of a motor 
car may be estimated as follows: 

Single-chain, with direct drive on the high 
speed, between the motor and rear axle—85 per 
cent. 

Two-chain drive, from motor to speed-change 
gear, from speed-change gear to rear axle—75 
per cent. 

Quarter-turn or right-angle drive, with dou¬ 
ble-chain drive to free rear wheels—70 per 
cent. 

Longitudinal shaft drive, with universal 
joints and bevel gear in differential case—65 
per cent. 

Transmission Shaft. The square transmis¬ 
sion-shaft used on several highest-powered cars 
is a nickel steel forging with .25 to .30 per cent 
of carbon. The treatment is about as follows: 
First heated in lead bath, then transferred to 
the cyanide, where it remains 20 minutes, then 
dipped in cottonseed oil. The shaft then goes 
to the furnace and is heated to 1,400 degrees 
Fahrenheit. When removed from the furnace, 
only the part of the shaft upon which the slid¬ 
ing gears operate is dipped in oil. This class 
of steel before treatment averages 86,000 tensile 
strength, after treatment 125,000 to 130,000. 

Troubles—Throttle. Slowing down the speed 
of a motor by throttling the charge, should not 
be resorted to until the ignition has been re¬ 
tarded as far as possible. If the motor speed 
be reduced, by first throttling and then after- 


648 


The Automobile Hcmdbook 


wards retarding the ignition, or by a combina¬ 
tion of the two, it generally results in misfiring 
of the motor. 



THROTTLE 


Fig. 303 

A butterfly-valve or form of throttle com¬ 
monly used is shown in Figure 303. The valve- 
chamber A, has the valve B, operated by the 



Fig. 304 

lever C. The valve is located at anv suitable 

• * 

point in the admission-pipe D, between the car¬ 
bureter and the admission-valve of the motor. 









































The Automobile Handbook 


649 


A form of admission-valve governor or throt¬ 
tle is shown in Figure 304. The pressure of the 
spring on the admission-valve stem A is in¬ 
creased or decreased by means of the wedge B, 
acting- on the taper washer or collar C. The 
valve is located in the cylinder-head or combus- 
tion chamber D, of the cylinder E, and is op¬ 
erated by means of the rod F, through the bell- 
crank lever G, and link II. The bell-crank lever 
is carried by a bracket J, on the top of the cyl¬ 
inder, as shown. 

Tubing. Copper tubing is considerably used 
for piping the gas to the burners, but it is liable 
to erosion by the gas, and standard Vs-inch gas 
pipe is better and lasts longer. The 1 gas bag and 
rubber lamp connections should be kept clean 
and not painted, as is often done to correspond 
with the car, as paint rots the rubber, with the 
result that it is soon unserviceable, and must be 
replaced. When the rubber is to be washed, 
only water should be used and the goods should 
be carefully dried before putting them in ser¬ 
vice again. 

U and H Magneto. The particular feature of 
this magneto is that the starting spark is a 
maximum, whether the crank is turned slowly 
or fast. 

In the operation of the U and H magneto. 
Fig. 305, a low-tension current of electricity is 
generated by the rotation of the armature of 
the magneto. An interrupter, or timer, inter¬ 
rupts the flow of this low-tension current at the 


The Automobile Handbook 


proper time, this interruption causing a high- 
tension current, similar to that delivered by the 
induction coil of a battery ignition system, to 
be induced in the rotating armature by a pe¬ 
culiar arrangement of the windings of the arma¬ 
ture. The high-tension current is conducted to 
a so-called distributer, the duty of which is to 



U. & II. Magneto 


distribute the high-tension current to the spark 
plugs of the various cylinders in the proper se¬ 
quence of firing. The wiring diagram of the U 
and H magneto is shown in Fig. 306. 

The magneto consists of three pairs of per¬ 
manent hoiseshoe magnets, placed parallel, 
and having secured to each of their free ends 
a soft iron block. These blocks are exactly 




























































































































The Automobile Handbook 


651 


alike, and form a permanent magnetic field. 
They are bored so as to allow an armature to 
revolve between them. The armature is of the 
shuttle type, and is provided with a double 



winding. The inner or primary winding con¬ 
sists of a few layers of coarse insulated wire. 
The outer or secondary winding consists of a 
great number of layers of fine insulated wire. 
The beginning of the primary winding is 



































































652 


The Automobile Handbook 


grounded to the armature itself. The end of 
the primary winding is connected with the 
carbon brush 1, which is carefully insulated 
from the armature shaft. Brush 1 bears against 
the interrupter block screw 2, which in turn 
conducts the current to the interrupter block 3, 
and to the condenser plate 4. From the inter¬ 
rupter block 3 the current is .conducted by 
means of the platinum pointed interrupter con¬ 
tact screw 5 to the platinum contact on the 
interrupter lever 6. The interrupter lever 6 
has metallic contact with the body of the mag¬ 
neto, and is therefore grounded and in elec¬ 
trical connection with the beginning of the pri¬ 
mary winding. It will be seen that when the 
interrupter lever 6 is in contact with interrup¬ 
ter contact screw 5, the primary circuit is 
closed, and the primary winding of the arma¬ 
ture is short-circuited. 

The beginning of the secondary winding is 
connected to the end of the primary winding, 
being in fact a continuation of the primary 
winding. This fact should be borne in mind, 
as it has direct bearing upon the results at¬ 
tained with this magneto. The end of the sec¬ 
ondary winding is connected to the armature 
slip ring 7, which is thoroughly insulated from 
the armature. From the armature slip ring 7 
the current is conducted by means of the 
brushes 8-8 to the distributer slip ring 9, from 
whence it is led to the distributer brush 10 by 
means of the distributer brush spring seat 12 


The Automobile Handbook 


653 


The distributer plate 13 is provided with as 
many brass distributer segments 14, evenly 
spaced around the distributer bore, as there are 
cylinders to be fired, and as the distributer 
brush is revolved it comes into contact in suc¬ 
cession with the segments. These segments are 
in turn connected with the secondary terminals 
15, located at the top of the distributer plate, 
one terminal for each cylinder. From these 
terminals the high tension current is conducted 



Fig. 307 

U. & H. Magneto Interrupter 


by cables to the spark plugs of the cylinders, 
from whence, after jumping the gap it is con¬ 
ducted to the grounded end of the primary coil, 
through the primary coil to the beginning of 
the secondary winding, thus completing the sec¬ 
ondary or high tension circuit. 

U and H Interrupter. The interruption of 
the primary circuit is accomplished by the in¬ 
terrupter, as shown in Fig. 307. This device 
consists of the interrupter plate 16, which is 


















654 


The Automobile Handbook 


located in the interrupter 17. Attached to the 
interrupter plate 16 is a stud 18, upon which 
is pivoted the interrupter lever 6. The inter¬ 
rupter lever is provided with a platinum 
pointed contact screw 19, which is normally 
held by the flat spring* 20 in contact with the 
platinum pointed interrupter contact screw 5. 
The interrupter contact screw 5 is connected to 
the end of the primary winding, as already de¬ 
scribed. 

Keyed to the interrupter end of the armature 
shaft, and rotating positively with the arma¬ 
ture, is the interrupter cam housing 21. Se¬ 
curely attached to the interrupter cam housing 
is the interrupter cam 22, consisting of a ring 
of hard fiber, having on its inner face two pro¬ 
jections or cam faces 22A. 

The interrupter housing 17 is held in accu¬ 
rate alignment with the interrupter cam 22 by 
the construction of the rear end plate 23, and 
as the armature revolves the projections 22A- 
22A are brought into contact with the interrup¬ 
ter cam pin 24, causing a movement of the in¬ 
terrupter lever 6 sufficient to separate the con¬ 
tact screws 5-19, and thereby interrupt the pri¬ 
mary circuit twice in every revolution. As the 
projections 22A continue to revolve, the inter¬ 
rupter lever 6 instantly resumes its normal po¬ 
sition, and completes the primary circuit. The 
entire housing of the interrupter is easily re¬ 
moved for inspection, or adjustment by push¬ 
ing the spring clip 31 to either side. 


The Auto mobile Handbook 


655 


U and H Starting Device. The easy starting 
device used in connection with the U and H 
magneto is shown in Fig. 308. It consists of 
an arrangement whereby the armature is given 
a partial revolution at a very high rate of 
speed, this partial revolution carrying poles of 
the armature across from one pole of the mag¬ 
netic field to the other, the highest speed oc¬ 
curring at the point where the maximum cur- 



Fig. 308 

Details of U. & H Starting Device 


rent is generated. The partial revolution at 
high speed may be produced at each revolution 
of tlu i armature by slowly rotating the starting 
crank, thus making it possible to start a motor 
directly on the magneto, with no more inconve¬ 
nience than is experienced in starting on batter¬ 
ies, the starting crank not requiring a contin¬ 
uous rotation, but simply an upward pull of 
half a revolution in the case of a four cylinder 





















































































656 


The Automobile Handbook 


motor. The speed at which the crank is rotated 
may be infinitely slow, yet at the proper time 
an intensely hot spark will be produced. 

These results are attained by having the ar¬ 
mature shaft G at the driving end journaled in 
the armature driver C, the shaft being perfectly 
free to rotate in its bearing D. Rigidly at¬ 
tached to the shaft G, and armature head is the 
driving flange F. The armature driver C is 
provided with two lugs. A, of peculiar form, 
180 degrees apart, which engage with corre¬ 
sponding surfaces P, formed on the driving 
flange F. These lugs serve both to prevent ro¬ 
tation in one direction, and to preserve the . 
proper relative positions between the armature 
driver C and the driving flange F, under nor¬ 
mal running conditions. A heavy helical driv¬ 
ing spring, E, of a large diameter, is placed be¬ 
tween the armature driver C and the driving 
flange F, and has one end securely attached to 
each. In assembling, this spring is put under 
sufficient tension to cause the lugs A to engage 
with their corresponding faces P, on driving 
flange F, and considerable effort is required to 
separate the lugs from the faces by reason of 
the spring tension. Milled into the driving 
flange is a ball slot. S’, in which a steel ball K. 
of approximately half an inch diameter, is 
loosely fitted, being free to move radially from 
a position close to the armature shaft, outward, 
until further movement is prevented by the 
driving spring E. Rigidly attached to the 


The Automobile Handbook 


657 


starting device casing is a cam ring, H, having 
upon its face a hardened cam-like projection, 
R. The form of this projection R is such that 
it will engage the steel ball K as it revolves 
with the driving flange F in one direction, but 
if turned in the other direction it simply pushes 
the ball out of its path. In the armature driver 
C is a depression B, into which the ball may 
slip at the proper time, and thereby clear the 
end of the cam R. 

Unit of Heat. The heat unit or British ther¬ 
mal unit (B. T. IT.) is the quantity of heat re¬ 
quired to raise the temperature of one pound 
of water one degree, or from 39° to 40° F., and 
the amount of mechanical work required to pro¬ 
duce a unit of heat is 778 foot pounds. There¬ 
fore the mechanical equivalent of heat is the 
energy required to raise 778 pounds one foot 
high, or 77.8 pounds 10 feet high, or 1 pound 
778 feet high. Or again, suppose a one-pound 
weight falls through a space of 778 feet or a 
weight of 778 pounds falls one foot, enough 
mechanical energy would thus be developed to 
raise a pound of water one degree in tempera¬ 
ture, provided all the energy so developed 
could be utilized in churning or stirring the wa¬ 
ter. 

Valves. A valve in a very bad or pitted con¬ 
dition causes bad compression, and the exhaust- 
valve should be ground occasionally. After 
grinding the exhaust-valve be sure that there 
is ample clearance between the valve and the 


658 


The Automobile Handbook 


lifter. It should have not less than one thirty- 
second of an inch, otherwise when the valve be¬ 
comes hot it will not seat properly, poor com¬ 
pression being the result. In grinding a valve 
there is no occasion to use force, and the grind¬ 
ing should be done lightly, the valve being 
lifted from time to time so that any foreign 
substance in the emery will not cut a ridge in 
the seat, or the valve itself. After grinding the 
valve always wash out the valve seat with a 
little kerosene, and be careful that none of the 
emery is allowed to get into the motor cylinder. 

Valves which need reseating should first be 
ground in place with fine emery and oil, then 
finished with tripoli and water. 

A good mixture for grinding valves may be 
made by using fine emery and cylinder oil 
mixed in the form of a paste convenient to 
work with. 

Exhaust-Valve Sticking. Sometimes a mo¬ 
tor may suddenly stop from the failure of the 
exhaust-valve to seat properly. This may be 
due to the warping of the valve, through the 
motor having run dry and become hot. or it 
may be from the failure of the valve spring, or 
the sticking of the valve-stem in its guides. The 
valve should be removed, and the stem cleaned 
and scraped, or straightened if it requires it, 
until it moves freely in the guide, and the 
spring is given its full tension. If the valve 
still leaks so that the motor will not start or 


The Automobile Handbook 


659 


develop sufficient power, the valve will have to 
be ground into its seat. 

Auxiliary Air-Valve. It has been deter¬ 
mined from the result of experiments that to 
get the maximum power at any speed from a 
gasoline motor equipped with a float-feed car¬ 
bureter, the jet of the carbureter must have a 
larger opening for low speeds than for high 
speeds. As this practice would require a very 
delicate adjustment it consequently becomes 
almost impracticable, because necessitating a 
constantly varying regulation for each frac¬ 
tional variation of speed of the motor. The 
difficulty may be obviated by the use of an aux¬ 
iliary air-valve, located in the induction-pipe 
close to the inlet-valve of the motor. 

The jet of the carbureter is set for the maxi¬ 
mum quantity of gasoline at the slowest speed 
of the motor, and as the speed is increased the 
auxiliary air-valve comes into action and re- 
duces the supply of air passing through the car¬ 
bureter, thereby reducing the suction or partial 
vacuum at this point, and maintaining a con¬ 
stant quality of mixture at all times. 

Valve-Stems—Weak Points of. Recent ex¬ 
periences call attention to the fact that a 
change is necessary in the construction of 
valves, or rather that part of the valve attach¬ 
ments adopted, by some designers, to hold the 
spring in position. This remark applies partic¬ 
ularly to the vertical type of valve, but the 
same defect has been found in horizontal valves. 


(560 


The Automobile Handbook 


Opinions vary as to the best method of secur¬ 
ing the springs in position, some designers pre¬ 
ferring pins, either round or square, others the 
nut and cotter. Both have points in their fa¬ 
vor and some common faults. It is doubtful, 
however, whether the method of slotting, or 
broaching the stem, and then using a key for 
securing the spring, is as secure as that of using 
a nut and pinning it to prevent its becoming 
loose. Under the latter plan there is no drill¬ 
ing of the stem except for a small cotter or 
split pin and the nut carries the strains, whereas 
in the other method the strain bears on the 
stem at the point at which the slot is made for 
the key, the latter being the means by which 
the strain is carried to the stem. Especially is 
the slotting of the stem unsafe when the stem 
is hardened, for vibration plays havoc with the 
valve. Many breakages have occurred from 
this cause and the question has become serious. 
While it is a fact that both kinds have suffered, 
the nut method of fastening is to be preferred, 
from the fact that even though the split pin 
may break and drop out, and the nut become 
loose, the trouble can be temporarily remedied 
by an extra piece of wire, while the slotted 
stem breaks off at a point where the metal is 
thinnest and makes the valve useless. 

Timing the Valves. The movement of the 
valves should always be timed to give the 
proper results. This is an important point to 
remember. The exhaust-valve cam shaft on a 


The Automobile Handbook 


661 


four-cycle motor is usually driven by the two to 
one gear on the crank shaft, and if for any rea¬ 
son the gears are taken apart and put together, 
even if only one tooth is out of place, it will 
throw the valve and spark mechanism out of 
time. 

To ascertain if the exhaust-valve of a motor 
is properly timed, turn the flywheel over slowly, 
and notice at what points the exhaust-valve 
opens and closes, and when the ignition takes 
place. 

The exhaust-valve should open slightly be¬ 
fore the beginning of the inward stroke and 
close at the end of the same stroke. The next 
inward stroke is the compression stroke, when 
both valves should be closed. 

Butterfly-Valves. This form of valve is 
generally used in the admission-pipe between 
the carbureter, and the admission-valve of the 
motor, to regulate or throttle the supply of 
explosive mixture to the motor. 

Swing Check-Valve. Valves with a hinged 
disc, usually set at an angle of 45 degrees, are 
sometimes attached to the air-inlet opening of 
the carbureter to prevent leakage of the mix¬ 
ture, when atmospheric or suction operated 
admission-valves are used. 

Globe Valves. This form of valve is usually 

«/ 

placed in the outlet pipe of the gasoline tank, 
to shut off the gasoline from the carbureter. 

Valve Clearance. A large number of motors, 
especially old ones, are unnecessarily noisy be- 


662 


The Automobile Handbook 


cause of superfluous clearance between the 
valve lifters and the valves, and a great part 
of the noise may be eliminated simply by the 
expenditure of a little time and care in reduc¬ 
ing this clearance to the minimum. Every valve 
cam, no matter what its shape otherwise may 
be, is tangential at the first and last portions of 
the valve’s movement. The sooner the valve 
takes hold of the cam on the lift, and the later 
it lets go on the descent, the slower will be the 



movement of the valve at these instants, and 
the less will be the shock both of the lifter on 
striking the valve stem, and of the valve head 
on meeting its seat. Fig. 309 shows this clearly. 
The tangent line A B starts at A, and during 
the arc D C the rise of the cam amounts only 
to a minute distance A D. During the follow¬ 
ing equal angle, however, the lift is three times 
as great. 

The objection to an excessive clearance is not 






The Automobile Handbook 


663 


simply the vertical hammering, but the sidewise 
pressure imposed on the valve-lifters by the 
cams, particularly at the instant of opening the 
exhaust-valves. If it were possible to operate 
the valves with no clearance whatever, and if 
there were no lost motion, and if the whole 
mechanism were ideally rigid, the line of pres¬ 
sure of the cam at the instant could be said to 


i 



be vertical, and there would be no side thrust 
till the valve was off its seat and the pressure 
of the gases on the valve was partly equalized. 
As the matter actually stands, however, there is 
a side thrust which is considerably increased 
by unnecessary clearance, as comparison of 
Figs. 310 and 311 clearly shows. In Fig. 
310 there is no clearance, and the tangent to 








664 


The Automobile Handbook 


the line of contact is horizontal. In Fig'. 311 
there is a clearance, AB. The thrust acts at 
right angles to the tangent along the line C D, 
and if C E represents by its length the force 
required to overcome the pressure on the valve 
and the force of the spring, there is a horizontal 
thrust equal to D E. It goes without saying 



that valve-lifters thus adjusted will wear loose 
in the guides faster than they should. As the 
gas pressure on the valve head may amount to 
30 or 40 pounds per square inch the instant be¬ 
fore the valve is open, there is an evident tend¬ 
ency to wear a hollow in the cam at the pre¬ 
cise point where it starts the exhaust valve from 
its seat. Evidently, moreover, the smaller the 











The Automobile Handbook 


665 


clearance, the greater will be the leverage of 
the cam, and the smaller will be its wearing 
tendency. 

The precise amount of minimum clearance is 
hard to state arbitrarily. The thickness of a 
business card or about 10-1,000th of an inch is 
ample allowance for the expansion ok valve 
stems for the average length. 

Valves—Lead of. The higher the speed of the 
motor the greater the necessity for giving both 
the exhaust, and the inlet valves what has come 
to be known as a “lead,” in that they open 
before the completion of the particular part of 
the cycle that they are intended to perform. It 
must be borne in mind that time is required to 
set a thing in motion and to stop it, regardless 
of its form or weight, and this is true of a gas, 
which has inertia the same as other substances. 
Further, an appreciable period, though very 
short indeed, is required for the creation of the 
vacuum in the cylinder. The gas does not rush 
into the combustion chamber the moment the 
inlet valve opens; the piston must have traveled 
downward a bit before this takes place and the 
column of gas then rushing in attains an in¬ 
creasing velocity as the piston approaches the 
lower center. In fact, it is at its greatest speed 
when the piston reaches the lower dead center 
so that the first part of its return travel has 
little or no effect on the incoming gas, which 
accordingly continues to pour into the cylinder, 
until the piston reaches a point on its upward 


7 


666 


The Automobile Handbook 


stroke, where its compression is sufficient to 
overcome the inertia of the stream of gas, and 
this is the point at which most designers of 
high-speed engines set the inlet valve to close, 
thus permitting of the suction of the greatest 
possible quantity of fresh gas. 

•Vibrator Coil—Current Used With. A prop¬ 
erly designed vibrator coil will not use as much 
current as a plain jump-spark coil. The self- 
induction in the primary circuit caused by the 
high frequency of the pulsations tends to check 
the flow of the current to a far greater extent 
in a vibrator coil than in a plain jump-spark 
coil. 

Vaporizers. Vaporizers are much less com¬ 
mon now than they were several years ago. 
They are very wasteful of gasoline, and require 
frequent adjustment to make them supply the 
proper mixture. One of their most obvious dis¬ 
advantages is, that the gasoline will flow more 
rapidly to the needle valve when the tank is 
full than when it is nearly empty, on account 
of the difference in pressure due to the height 
of the surface above the valve. The proportion 
of air to gasoline is also not entirely constant 
when the engine speed changes, or when the 
engine is throttled. There is a tendency for 
the mixture to be too rich at high engine speeds, 
since the flow of gasoline is not only due to the 
pressure from the elevation of the tank, but is 
also due to the partial vacuum existing in the 
mixing chamber, and to the velocity of the air. 


The Automobile Handbook 


667 


Even if no vacuum existed in the mixing cham¬ 
ber and if the gasoline had no pressure at the 
needle valve, the gasoline would still be drawn 
into the air by the velocity of the latter. It 
will thus be seen that there are four factors 
that affect the proportions of the mixture; 
namely, the head of the gasoline in the tank, the 
lift of the needle valve, the vacuum in the mix¬ 
ing chamber, and the velocity of the air. What 
is really desired is that only the last named of 
these four factors should be operative; or, in 
other words, that the velocity of the gasoline 
.jet should be in direct proportion to the veloc¬ 
ity of the air. This is not attained in the type 
of carbureter just described. 

Vapor Tension. The saturation point for any 
given vapor depends on the temperature. If 
the temperature is increased, more vapor will 
be given off, and a reduction of the temperature 
will cause a portion of the vapor to condense. 
An increase in the quantity of vapor in a given 
space implies an increase in its pressure, and 
consequently it follows that the pressure at 
which saturation occurs depends on the tem¬ 
perature. 

Every vapor exerts a certain amount of pres¬ 
sure, although the pressure may be much less 
than that of the atmosphere. Even the mer¬ 
cury vapor in the almost perfect vacuum of the 
barometer has a slight amount of pressure. The 
vapors of volatile liquids, or liquids that vapo¬ 
rize readily, are given out much more abund- 


668 


The Automobile Handbook 


antly, and their pressure under the same con¬ 
ditions is therefore much greater. For the 
same temperature, each liquid has its own 
vapor pressure. At 68° F., the pressure of sat¬ 
urated ether vapor is twenty-five times the pres¬ 
sure of saturated water vapor. The pressure 
exerted by any vapor in its saturated state is 
often spoken of as the vapor tension for that 
temperature. 

Water Circulation. There are two systems of 
water circulation in use for cooling the cylin¬ 
ders of explosive motors: The natural or ther¬ 
mo-siphon system and the forced water circu¬ 
lation. 

In natural or thermo-siphon water circula¬ 
tion the fact that cold water is heavier than hot 
water is taken advantage of. A head of water 
is obtained by placing the tank above the level 
of the cylinder water-jacket, and as the water 
in the jacket is heated by the combustion, the 
cooler water from the tank flows in, forcing the 
heated water in the tank to take its place, and 
in this manner an automatic circulation of wa¬ 
ter is set up. The pipes must be so arranged 
that they offer every facility for the free circu¬ 
lation of the water, the cold water leaving 
through a pipe at the bottom of the tank and 
entering at the lowest point of the cylinder, 
while the hot water leaves the top of the cylin¬ 
der and enters the tank at the side near the 
top. The water circulation, though automatic, 
is very slow, and for this reason requires a 


The Automobile Handbook 


669 



DIAGRAM 


Fig. 312 

larger body of water to produce as good a cool¬ 
ing effect as a forced circulation. 

In forced circulation a rotary pump is used, 











































































670 


The Automobile Handbook 


the direction of the how being such that the 
water passes from the pump to the cylinder, 
thence to the radiator, on to the tank, and then 
through the pump again, thus completing its 
circuit. The water in this way gets the maxi¬ 
mum cooling effect from the radiator, and the 
body of water in the tank is kept cool. On ac¬ 
count of the high speed of a gasoline automo¬ 
bile motor, and the comparatively small amount 
of power required to circulate the water, ro¬ 
tary pumps are much used. As there are no 
valves to get out of order, and high speed is 
obtainable, this type of pump is very suitable 
for automobile use. 

The upper and lower views in Fig. 312 show 
the principles of operation of the gravity or 
thermo-siphon, and the forced or pump circu¬ 
lating systems respectively. The volume of 
cooling water required for the tubular type of 
radiator is about 13 cubic inches per horse 
power. 

Watt-Hour—Definition of. A current of one 
ampere flowing in an electric circuit, with an 
electro-motive force of one volt, is equal to 
one volt-ampere or one watt. The voltage of a 
circuit, multiplied by the rate of the current 
flowing in amperes, gives the rate of work, or 
energy expended in watt-hours. 


Elements 

Hydrogen, II. 

• 

Atomic 

Weights 

Oxygen. O. 


. TO 

Nitrogen. N . 


. 14 

Carbon. C . 



Sulphur, S. 


. 32 







The Automobile Handbook 


671 


Weight—Atomic. The atomic weight bears 
a direct relation to specific gravity. 

The atomic weights of the elements most 
often found in fuels are given in Table 18. 

With the aid of these atomic weights, the 
composition of any substance by weight can be 
found when its formula is known. Take, for 
example, water, H 2 0, which has two atoms of 
hydrogen to one of oxygen, and multiply the 
number of atoms of each by the atomic weight 
of the element; the results will be the parts by 
weight of the elements. Thus, 

i 

2 atoms of H X atomic 

weight, 1 = 2 parts of H 

1 atom of 0 X atomic 

weight, 16 = 16 parts of O 

18 parts of H 2 G 

Then, the water is composed of 2 /18 = 11.11 
per cent of hydrogen, and 16/18 = 88.89 per 
cent of oxygen. 

As another example, take carbon dioxide, 
C0 2 , in which, 

1 atom of C X atomic 

weight 12 = 12 parts of C 


2 atoms of 0 X atomic 

weight, 16 = 32 parts of O 


44 parts of C0 2 



Fig. 313 

Section Through Rear Wheel with Combination Brake 
Drum and Inner Flange 








































































































































































































































































The Automobile Handbook 


673 


Hence, C0 2 contains 12/44 = 27.27 per cent 
of carbon, and 32/44 = 72.73 per cent of oxy¬ 
gen. From these examples it is plain that the 
weight of the molecule, or the molecular weight, 
of water is 18, and that of carbon dioxide, 44. 

Wheels. The wood work of all wheels should 
be of selected grades of second growth hickory, 
or equally good growths of other hard woods. 
In the driving wheels the twisting moment of 
the motor is transmitted to the spokes of the 
wheels, and this torsion must be resisted by 
the wood at the miter, therefore, if the hub 
Hanging is not clamped tight there is danger of 
the joints “working,” which will soon lead to 
something worse. When the hub clamping 
bolts are tightened up they should be so pinned 
that they will not turn with the nuts because 
if the bolts do turn it will be impossible to 
apply sufficient pressure, and the clamping ef¬ 
fort will be insufficient. Fig. 313 shows a hub 
in which the clamping bolts are prevented from 
turning by means of a triangular shaped exten¬ 
sion just under the bolt heads, which engages 
a slot in the flange. In this hub the flange is 
made integral with the brake drum, which also 
serves for the sprocket wheel, and the torsional 
effort is taken by integral metal at all points, 
thus relieving the wood work from shock. The 
nuts used on the clamp bolts shown in Fig. 313 
are castellated, although it is not necessary to 
use castellated nuts unless the flanges have to 
be removed, which in modern construction is 


k—i^o->! 







































The Automobile Handbook 


675 


the exception, rather than the rule. In ordi¬ 
nary practice if the wood is thoroughly sea¬ 
soned, plain nuts, if screwed up tight will hold 
without resorting to the method so common in 
shop practice of riveting the ends of the bolts 
over the nuts. The elastic nature of the wood 
will serve to hold the nuts in place. Regard¬ 
ing spokes, a certain symmetry of contour is 
necessary if they are to be machine made. Fig. 



Fig. 315 

Section of a Hub at the Miter Showing Depth of Flange 
and Method of Clamping 

314 shows a spoke in which all the advantages 
known to wheel making are embodied, and the 
depth of flanging is that which experience dic¬ 
tates as adequate. The dimensions of the spoke 
are shown in detail in the cut. The brake drum 
is bolted to the spokes at a considerable radius, 
thus eliminating excess strain on the wood 
work. 

The strength of the spoke depends in a large 


























































676 


The Automobile Handbook 


measure upon its thickness in the axle plane at 
the hub flange, which in Fig. 314 is 1 % in. The 
second point of importance is at A, B, where 
the largest diameter is also 1 % in., but in the 
plane of the wheel instead of the axle. At the 
tenon engaging the felloe, this spoke is 1% in., 
in its major diameter, which is the plane of the 



Fig. 316 

Section of Felloe Depicting Tenon and Method of 
Wedging Which will Split the Felloe 

axle, while in the plane of the wheel the minor 
diameter of the elliptical section is 1 3/16 in., 
which dimension prevails in this plane from 
point A. B, out to the felloe. In some types of 
spokes the section at the engagement of the fel¬ 
loe is round, and reduced gradually to the sec¬ 
tion at A, B. Fig. 315 shows a section of the 



































The Automobile Handbook 677 

hub of another type of wheel, in which the 
radial depth of flanging is 2*4 in., and the axle 
thickness of the wood is 2 i/g in. This wheel 
may be used on a 60 II. P. car, and will serve as 
a safe example of depth of flanging, as well as 
a guide in fixing the shear section of the spokes 
for stresses induced, when cars of great power 
skid, provided the wheel is not dished. Fig. 
316 shows the same spoke at its engagement 
with the felloe, indicating the manner in which 
the spoke is wedged into the felloe. 



Figure 317 shows the Scharz type of wheel, 
indicating the method of overlapping the mi¬ 
ter, thus making it possible to true up the wood 
work independent of the hub. Fig. 318 shows 
a section of the hub, spoke and felloe of a 
dished wheel, and it will be seen that the felloe 
is not in the plane of the miter, and the dish of 
the wheel is outward. When a car is running 
at a comparatively high speed rounding a 
curve, the outer wheels are stressed in such a 
















678 


The Automobile Handbook 


manner that the tendency is to set a dish in 
them exactly opposite to the dish given by the 
wheel maker. 

The shorter the spokes are, the greater will 
the dishing have to be in order to insure that 
the spokes will be enough longer than the radial 



Section of a Wheel Showing the Dish, Which Has 
Strength to Resist Skidding and Lateral Stresses 

distance from the hub end of the spokes to the 
bearing against the felloe, to serve as members 
in compression, and the rim on the felloe will 
have to do the work. As the cut shows, the ex¬ 
cess length of spokes marked “difference,” 
represents the versed sine of the angle of the 
spokes. 















The Automobile Handbook 


679 


Dishing transfers skidding stresses to the 
rim, induces compression moments in the 
spokes, and thus eliminates shearing moments 
at the flanges of the wheels, which makes it pos¬ 
sible to reduce the width of the spokes in the 
plane of the axle near the hub. This will, how¬ 
ever, necessitate sufficient strength in the sta¬ 
tionary rim to withstand the additional strain. 
In automobile wheels, if the rim proper is 
placed over a stationary rim, as it is in de¬ 
mountable work, the chances of wheel trouble 
may come, as in ordinary carriage wheels, by 
what is known as “rim bending.” A rim bound 
wheel is liable to warp and become unsafe, es¬ 
pecially if allowed to stand in a damp place. 
Owing to the increasing scarcity of second 
growth hickory, wire wheels are coming into 
favor to a considerable extent, but the princi¬ 
pal objection to their use is their liability to 
rust. However, there is no doubt that a high 
nickel steel, in which corrosion will be practi¬ 
cally eliminated, will eventually be made for 
wire spokes. As to the strength of wire wheels 
there can be no question, provided, of course, 
that the steel is of good quality. 

Wipe Spark. A form of primary sparking 
device which is in use on some gasoline motor¬ 
cars, but principally used on marine and sta- 
tionary gasoline motors. A form of wipe or 
touch spark is illustrated in Fig. 319, in which 
the make and break is between a rocker arm 
located in the side of the combustion chamber, 


680 


The Automobile Handbook 



Fig. 319 

A—Rocker contact arm. D—Insulated busking. 

B—Spring-actuated plunger. E—Mica insulation. 

C—Coil spring. F—Lock nut. 

G—Terminal nut. 

TABLE 19. 


RESISTANCE AND CARRYING CAPACITY OF BARE AND INSULATED 

COI*PER WIRE. 


B. & S. 
Gauge. 

Diameter 
in inches. 

Ohms per 
thousand 

Carrying Capacity in 
Amperes. 


feet. 

Insulated. 

Bare. 

6 

.162 

0.411 

65 

65 

r* 

i 

.144 

0.519 

56 

50 

8 

.128 

0.654 

40 

46 

9 

.114 

0.824 

39 

39.2 

10 

.101 

1.040 

32 

. 32.5 

It 

.091 

1.311 

27 

27.8 

12 

.081 

1.653 

23 

24 

13 

.072 

2.084 

19 

19.0 

14 

.064 

2.628 

10 

10.3 

ir> 

.057 

3.314 

10 

13.9 

10 

.051 

4.179 

8 

12.0 

17 

.045 

5.269 

0 

9.8 

18 

19 

20 

.040 
, .035 

.032 

6.045 

8.01 7 

10.560 

5 

8.1 

7.0 

6.0 







































The Automobile Handbook 


681 


and a spring plunger immediately above the 
end of the arm, and in the center of the cylinder 
head. The reference table given in connection 
with the drawing will explain the construction 
clearly. 

Wiring for Ignition Circuits. Multi-cylinder 
gasoline motors may have the wiring of their 
ignition circuits arranged in various manners, 
as follows: 

Two-Cylinder Motor. Single-coil, with the 
two spark plugs in series with each other. A 
four terminal coil is necessary to use with this 
arrangement. 

Duplex-coil, with the two spark plugs inde¬ 
pendently connected to the secondary winding 
of the coil, one end of each secondary wire be¬ 
ing grounded to the frame or motor. 

Four-Cylinder Motor. Two coils, with each 
pair of spark plugs in series with each other. 
Two four-terminal coils are necessary with this 
arrangement. 

Four coils, with the four spark plugs inde¬ 
pendently connected to the secondary winding 
of the coil, one end of each secondary wire be¬ 
ing grounded on the frame or motor. 

The wiring for the ignition circuit of a four- 
cylinder motor is illustrated in Fig. 320. The 
commutator, quadruple coil, spark plugs, and 
duplex battery system are plainly shown. 

Wiring Troubles. In a single-cylinder motor 
the complete breakage of a wire or the loosen- 


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The Automobile Handbook 


ing of a connection, or the displacement of the 
wire leading to the spark ping will cause an 
instant stoppage of the motor. In a multi-cyl¬ 
inder motor such an accident will probably 
slow the car, and cause one cylinder to miss, 
with the result probably of explosions in the 
muffler. 

Wire-Drawing of Mixture in Carbureters. 

Frequently it is observed that the intake to the 
carbureter is so restricted that noise issues, and 
a little further investigation in such cases will 
disclose, in all probability, that wire-drawing is 
one of the ills. It is not alone the noise that is 
objectionable in such cases; the power of the 
motor will be less, due to the restriction which 
has the effect of reducing the weight of mix¬ 
ture that enters into the cylinders, and the 
power of a motor is undoubtedly proportional 
to the weight of mixture that enters the cylin¬ 
ders, assuming, of course, that the same is in 
acceptable form, and that it is completely 
burned. True, there must be a depression in 
the carbureter in order that there will be a dif¬ 
ference in pressure, so that gasoline will he 
sucked into the train of air; equally true, it is 
of the greatest importance to have the depres¬ 
sion as low as possible in order that the power 
of the motor will be a maximum. If the depres¬ 
sion is but slight, provided the carbureter is 
properly designed, the amount of fuel entrained 
will be adequate for the purpose. If, on the 
other hand, the depression is very large and 


684 


The Automobile Handbook 


holds considerable fuel, it will soon be found to 
be wasteful of the liquid. 

Wood Alcohol for Cooling. The idea in using 
alcohol in the cooling system is to get away 
from the use of water. In other words, the 
freezing point of the liquid used must be low¬ 
ered to prevent freezing in the system, and the 
consequent disruption, which is bound to fol¬ 
low if the solution solidifies, since then bulk 
increases and is irresistible. It would seem 
quite out of place to purchase alcohol for the 
purpose, were the same half water, since water 
is to be displaced in the system. In the pur¬ 
chase of alcohol then, for the purpose, care 
should be exercised to order the same as free 
from water as possible. 

According to the United States Pharmaco¬ 
poeia, “alcohol” should hold 91 per cent alco¬ 
hol and 9 per cent water, “proof spirits” only 
holds 55 per cent of alcohol, and “absolute al¬ 
cohol” will run about 98 per cent of alcohol 
with 2 per cent water. An alcohol-meter reads 
Zero (o) in water and 100 if there is no water 
present. The alcohol-meter, then, shows by its 
workings the percentage by volume of alcohol 
present. 

Because of the high price of grain alcohol, 
the formula for which is C 2 H 6 0, it is customary 
to use wood alcohol, the formula for which is 
CH 4 O, and because of this difference in the 
composition of the two grades of alcohol, the 
alcohol-meter should be purchased to use with 


The Automobile Handbook 


685 


wood alcohol on the one hand, or with grain 
on the other, depending upon the kind of alco¬ 
hol taken in any given case. 

Xardell Muffler. In the Xardell muffler a 
vacuum is employed to create a suction upon 
the exhaust gases coming from the engine. The 
muffler Consists of an elongated cylinder di¬ 
vided into two compartments, the smaller per¬ 
fectly air-tight acting as the vacuum chamber; 
the second, or large compartment, designed to 
silence the exhaust, divides the gases into innu¬ 
merable small jets and finally delivers them 
through an open port. According to test, with 
a pressure gauge attached to the muffler and 
the vacuum gauge attached to the vacuum 
chamber, the exhaust from a four-cylinder mo¬ 
tor with 5-inch bore was turned through it 
with a result that no pressure was shown under 
gauge attached to the muffler, and the pulsating 
vacuum indicated on the gauge attached to the 
vacuum chamber. This experiment apparently 
showed that immediately after the explosion 
the vacuum formed in the muffler relieved itself 
by drawing gases from the exhaust pipe, which 
naturally worked against any back pressure on 
the motor. 

Zero—Absolute. The freezing point was 
chosen as the zero point of the centigrade scale. 
When the Fahrenheit scale was invented, the 
zero point of the thermometer was placed 32° 
below the freezing point, as that was the lowest 
temperature that could then be obtained, and 


The Automobile Handbook 


tm 

it was supposed that it was impossible to obtain 
a lower one. From the results of experiments 
and from calculations, however, it has been 
concluded that at 461.2° F. below zero, or 
493.2° F. below the freezing point, there is 
absolutely no vibration of the molecules and 
consequently no heat. This is therefore called 
the absolute zero, and all temperatures reck¬ 
oned from this point are called absolute tem¬ 
peratures. Absolute zero has never been 
reached, the lowest recorded temperature being 
in the neighborhood of —400° F. 


STARTING AND LIGHTING DEVICES 


Self-Starters. One of the most important of 
the late developments in motor-car construction 
is the installation of mechanical starting de¬ 
vices, by which a powerful impulse is given to 
the motor before the explosions in the cylinder 
occur. Thus cranking by hand is eliminated, 
driving is made more practicable for women, 
and the safety, convenience and personal com¬ 
fort of the motorist are increased. 

Self-starting systems are of two principal 
types, operated (1) by compressed air, and 
(2) by electricity. Most cars of recent con¬ 
struction are now equipped with one of these 
two systems. 

Compressed Air Starters. In a typical air- 
pressure system the motor is operated with 
compressed air until regular explosions take 
place in the cylinders; the air supply is then 
shut off and the motor takes up its regular 
operations. 

The parts of this self-starter are as follows 
(see Fig. 321) : 1, a high-pressure, four-cylin¬ 
der air pump, for compressing air in a storage 
tank; 2, a pipe for carrying air from pump to 
storage tank; 3, a pipe which carries air from 

687 



688 The Automobile Handbook 

tank to push valve on the dash; 4, a pipe which 
carries compressed air from the push valve to 
the “distributor”; 5, pipes through which air 
is carried from the distributor to the various 
cylinders; 6, poppet valves—one in each of the 
cylinders—by means of which compressed air 
from the distributor is admitted to the cylinder 
ready for the working stroke; 7, a pressure 
gauge on the dash, which keeps the operator 
informed of the amount of compressed air in 
the storage tank; and 8, a pump clutch, oper¬ 
ated by a foot pedal, which throws the gears 
of the air pump into mesh. 

The air pump in this system is driven by a 
silent drive chain from the water pump shaft, 
and operates only when the gears are thrown 
into mesh by pressing the pump clutch foot 
pedal. It is a simple device for compressing 
the air and delivers a steady flow to the storage 
tank. A pressure of 50 lbs. in the tank will 
start the motor under ordinary conditions, but 
it is advisable to keep the pressure at about 
150 lbs. 

The storage tank is carried beneath the body 
of the car and is tested for a pressure of 600 
lbs. to the square inch. 

The dash push valve opens the air line from 
the storage tank to the distributor and simul¬ 
taneously opens the cylinder valves so that air 
coming from the distributor through the pipes 
shown in Fig. 321 has ready access to the cyl¬ 
inders. When the foot is removed from the 


The Automobile Handbook 


(589 



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Fig. 321—Chalmers Air Pressure Starting Mechanism. 






























The Automobile Handbook 


i;90 


dash button, both the escapement valve and 
the cylinder valves are closed automatically 
and the compressed-air starter is shut off from 
the motor. 

The distributor sends charges of compressed 
air into the cylinders ready for the working 
stroke, in their order of firing. It is geared 
to the pump and magneto shaft and positively 
timed for feeding air. 

This type of self-starter is also used for the 
purpose of inflating tires by means of a special 
shut-off valve and hose. 

The principle of compressed-air starters is to 
admit air under 50 to 150 lbs. pressure from a 
generous reservoir directly to the motor cylin¬ 
ders at the beginning of each expansion stroke. 
This operates the motor without affecting the 
mixture in the cylinders. When running under 
air pressure the admission of the compressed 
air at almost the moment of the spark operates 
the same as an ignition, causing a rise of pres¬ 
sure in the cylinder. After it has performed 
its work this pressure is released by the ex¬ 
haust valve in the same manner as the burned 
gases are released when the motor is running 
under its own power. 

Electric Starters and Lighting. The use of 

an electric starting device in connection with 
the electric lighting system is regarded by 
many as the ideal plan for the automobile. A 
type of this system, used on many cars, is found 
in the Gray & Davis 6-volt electric starter, illus- 


The Automobile Handbook 691 

trated in Fig. 322. This, it is claimed, will 
start any engine, even the 5x7 6-cyl. motor. 

This system comprises two units: 1, the 
starting motor; 2, the dynamo for charging 



battery and lighting. The function of the dy¬ 
namo is to furnish current for lamps and cur¬ 
rent for the battery. The starting motor starts 
the engine. This motor is connected with the fly¬ 
wheel by gears, and when a starting pedal is 












The Automobile Handbook 


(m 



I 

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£ 


323—Wiring Diagram G. & D. Dynamo System. 













































































































The Automobile Handbook 693 

pressed the motor turns the flywheel and crank¬ 
shaft and keeps turning until the engine “picks 
up.” The starting motor then automatically 
ceases to operate. 

The dynamo system includes the following: 

1, a constant-speed dynamo, driven from the 
engine or jackshaft by gear or a silent chain; 

2, a governor, to take care of the varying speed 
of the engine; 3, an electric cut-out, to discon¬ 
nect the dynamo from the battery when run¬ 
ning below the charging speed; 4, a battery to 
operate the lights when the dynamo is not run¬ 
ning at the necessary speed or when the en¬ 
gine is stopped. This battery may also be used 
for firing the engine. 

1. The dynamo is of the compound-wound 
type, designed to run at a constant speed of 
1000 revolutions per minute. The system is so 
wired that the series field is carrying current 
only when the lights are burning. See Fig. 323. 

2. The governor is of the simple, centrifugal 
type, but operates a friction clutch of new de¬ 
sign. In operation the clutch slips just enough 
to hold the dynamo speed always at 1000 
r. p. m., whether the engine speed corresponds 
to a car‘speed of 13 or of 60 miles an hour. 

3. The electric cut-out consists of an elec¬ 
tro-magnet with a compound winding, the fine 
wire part of which is connected across the dy¬ 
namo terminals. Its function is, as stated, to 
disconnect the dynamo from the battery when 
the engine is running very slowly or is at rest. 


694 


The Automobile Handbook 


If an automatic switch of this nature were not 
in the circuit the battery would discharge 
through the dynamo when the dynamo was no 
longer maintaining charging voltage. 

4. A battery rated at 6 volts, 80-ampere 



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hour capacity at a discharge rate of 8 amperes 
is furnished with this system sufficient to carry 
the full lamp load for ten hours or the side and 
tail lamps for thirty hours. The arrangement 















































































The Automobile Handbook 695 

of the switch connections is such that the 
dynamo operates as a shunt-wound machine 
while charging the battery and as compound- 
wound when supplying the lamps directly. This 
gives the battery a tapering charge. 

The wiring for this system is plainly shown 
in the accompanying diagram. See Fig. 323. 

The Rushmore Engine Starter. The Rush- 
more electric starting motor, shown in Fig. 
325, acts directly on the flywheel without in¬ 
termediate gears, a pinion keyed fast on the 
motor shaft meshing with a gear on the fly¬ 
wheel rim. This pinion is normally out of en¬ 
gagement. The closing of the starting switch 
causes the pinion automatically to engage the 
flywheel gear before the armature starts rotat¬ 
ing. As soon as the engine picks up, the pinion 
automatically slides out of mesh, and remains 
out no matter how long the starting switch is 
held closed. There is no mechanism except the 
starting motor itself and the starting switch. 

When the starter is not in use the armature 
is held normally out of line endwise with the 
pole pieces by means of a compression spring- 
contained in and acting against the hollow 
armature shaft. Magnetic pull is employed to 
engage the pinion. The foot button starting- 
switch has three contacts. At the first pres¬ 
sure upon the button the armature is drawn 
into the field with great force while rotating 
slowly so that the pinion teeth will engage. 
After the gears are fully engaged the third 


The Automobile Handbook 


696 

contact applies the full force of the battery to 
turn over the engine. 

The motor is series wound and produces a 
strong torque on starting. As soon as the en¬ 



gine picks up, the accelerated speed causes the 
counter electro-motive force in the motor to 
reduce the current flow to a value too small to 
hold the armature in line with the pole pieces 
against the end pressure of the spring. The 










The Automobile Handbook 


697 


pinion then slips out of mesh and remains out, 
even with the circuit closed, because the cur¬ 
rent required to run the motor free is too small 
to overcome, the spring. The armature will 
not again move endwise into its working posi¬ 
tion until it has stopped and the switch is 
again closed. The turning force developed at 
the flywheel rim is rated at over 400 lbs., suffi- 


IRON 

BALLAST 

COIL 



Fig. 326—Diagram of Rushmore Lighting System. 


cient to start the largest engine with ease. The 
motor is wound for a 6-volt battery. 

Rushmore Lighting System. Essential ele¬ 
ments of this system are: 1, the dynamo; 

2, storage battery, 6-volt, of 80 to 160 ampere 
hours capacity, depending upon size of the 
headlights; 3, switch and terminal block on 





























698 


The Automobile Handbook 


dashboard, which simultaneously switches the 
headlights on or off and switches the ballast 
coil in or out of circuit; 4, wiring and circuit 
switches for small lamps. . 

Briefly the action of the dynamo is to reduce 
the strength of the field magnet at high speeds 
by means of counter excitation produced by a 
few turns of magnet wire, called a “bucking 
coil,” on the field poles. The amount of cur¬ 
rent passing through this bucking coil is deter¬ 
mined automatically by the varying resistance 
of a small coil of iron wire, called the “ballast 
coil,” which is made in the form of a cartridge 
fuse and carried in clips on the switchblock in 
the main line between the dynamo and the bat¬ 
tery. See Fig. 326. The effect of controlling 
the bucking coil by the current output is to pro¬ 
duce an approximately constant current at the 
higher speeds. 

U. S. L. Electric Motor Generator. In the 

system employed by the United States Light 
& Heating Co., with which many automobiles 
are now equipped, an electric motor generator 
is an integral part of the gasoline motor and 
furnishes current for starting and lighting. 
The system includes, besides the motor gen¬ 
erator, an automatic current regulator, an oil 
switch and a storage battery. 

The motor generator comprises a set of field 
coils, armature and commutator and brush 
ring. These parts replace the flywheel of the 
gasoline motor, being attached to the crank- 



The Automobile Handbook 


699 


shaft in its stead. They are inclosed in an 
aluminum case and dust ring. 

When a starting button is pressed down, the 
current from the storage battery starts the 



motor generator. This revolves the crankshaft 
of the gasoline motor. AVith the switch of the 
ignition coil in either magneto or battery posi¬ 
tion, the gasoline explosions commence. The 
foot starting button is then released, when the 










700 The Automobile Handbook 

electric motor automatically changes into an 
electric generator. As the speed of the gaso¬ 
line motor increases, the generator gradually 
begins charging the battery, restoring the cur¬ 
rent discharged during the starting operation. 
* An automatic regulator, controlling the cur¬ 
rent to the battery, is located in the center of 
the dash. It has a charging indicator, the func¬ 
tion of which is to show that the circuit is 
closed at the proper time, or at a speed of 12 to 
14 miles an hour, and that the circuit is open 
when the car speed drops below about 10 miles 
an hour or the motor stops altogether. The 
regulator consists of a compound-wound mag¬ 
net and a variable resistance with magnet bar 
and contacts for controlling field current in 
the generator. 

The oil switch is included in this system to 
change the electric motor into an electric gen¬ 
erator upon the release of the starting button. 

This and other electric starting devices are 
designed for the sole purpose of starting, and 
not of running the car. There is often a strong 
temptation, however, to make them perform 
excess duty. This should be avoided as much 
as possible. If a driver has occasion to make 
repeated demonstrations of the starting fea¬ 
ture without running the car, he should always 
allow the gasoline motor to run for at least a 
minute or two at a fair speed—800 or 1000 
r. p. m.—between starts. This will replace the 
current required for starting. 




The Automobile Handbook 701 


















































































702 The Automobile Handbook 

Delco Cranking and Lighting System. The 

Delco motor-generator is another device ex¬ 
tensively used for starting the gasoline motor 
and supplying current for lighting purposes. 



In its first function it is a series-wound motor 
with a spur gear pinion upon the end of the 
armature shaft nearest the flywheel. Inter¬ 
posed between this pinion and the gear teeth 
cut in the periphery of the flywheel is a pair 






The Automobile Handbook 703 

of gears adapted to slide along and revolve 
upon an intermediate shaft. The sliding action 
causes one of these gears to engage with the 
motor pinion, while the other meshes with the 
gear teeth upon the flywheel. 

A positive, one-way clutch is incorporated 
as part of the intermediate gear, for the pur¬ 
pose of permitting the engine to run ahead of 
the motor during the short time that the gears 
may be enmeshed while the engine is running 
under its own power. 

In performing its function as a charging unit 
the motor-generator resolves itself into a shunt- 
wound generator, driven from the engine by 
means of a shaft extended from the camshaft 
gear housing. The generator is driven at 
crankshaft speed, and in order to compensate 
for the higher ratio when the unit is in start¬ 
ing relation to the engine, a second one-way 
clutch is provided adjacent to the forward 
housing. This clutch permits the armature to 
run ahead of the driving shaft. 

A voltage regulator, controlling the amount 
of current flowing from the generator to the 
storage battery, and a cut-out relay are in¬ 
cluded in the Delco system. The function of 
the latter unit is to close the circuit between 
the generator and the storage battery when the 
generator voltage is high enough to charge the 
storage battery. It also opens the circuit as 
the generator slows down and its voltage be¬ 
comes less than that of the storage battery, thus 


704 The Automobile Handbook 

preventing the battery from discharging back 
through the generator. 

In operating the Delco starting device on 
a typical car, when the push button on the 
lighting switch box is depressed, it closes a 
circuit and two things are accomplished: Cur¬ 
rent flows from the storage battery through a 
magnetic latch coil circuit and also flows 
through the generator windings, causing the 
armature to rotate slowly so that the starting 
gear will mesh into the motor pinion and with 
the teeth on the flywheel. The energizing of 
the magnetic latch coil causes the mechanism 
which operates the starting transmission and 
the generator switch to be linked to the clutch 
pedal shaft and consequently to be thrown 
into operation by the depression of the clutch 
pedal. 

When pushing forward on the clutch pedal 
to throw these gears into mesh, if it should 
happen that they are in such a position that the 
ends of the teeth in the clutch gear come 
against the ends of the teeth in the flywheel, 
instead of the teeth of one sliding between the 
teeth of the other, the operator should be care¬ 
ful not to try to force them. Simply let the 
clutch pedal come back a little and try again. 
By that time they will probably have changed 
their relative positions sufficiently to allow the 
teeth to mesh properly. 


Reference Tables 


501 Froiit axle with yokes and spring supports. 

502 Eight steering knuckle. 

503 Left steering knuckle. 

504 Front springs. 

505 Front spring clips with cross pieces. 

506 King bolts and nuts. 

507 Inside annular front bearing. 

508 Outside annular front bearing. 

509 Nuts for spindle of knuckle. 

510 Lock washers for nuts on spindle. 

511 Steel dust washers. 

512 Felt dust washers. 

513 Front connecting rod complete with adjusting 

ends. 

514 Adjusting end right hand thread front. 

515 Adjusting end left hand thread front. 

516 Cone screws, nuts and brass (pones for front 

adjusting ends. 

517 Eear connecting rod complete, adjusting end 

and ball rod adjuster. 

518 Adjusting end rear connecting rod. 

519 Cone screws, nuts and brass cones for rear con¬ 

necting rod. 

520 Ball rod adjuster with bolts. 

521 Ball rod with adjusting ring. 

522 Eight hand front connecting rod lock nut. 

523 Left hand front connecting rod lock nut. 

525 Bolts for holding spokes in hubs. 

526 Spring clip holders. 

527 Hardened washer for knuckles. 

528 Ball rod brasses. 

529 Eear connecting rod lock nut. 

5-30 Front wheels with rims without tires and with* 
out bearings. 

531 Tires front and rear. > " .L 

705 


706 The Automobile Handbook 

532 Washer inside front dust cap for holding in 

outside bearing. 

533 Front dust caps. 

534 Bear dust caps. 

535 Rear wheels with rims without tires and with¬ 

out bearings. 

536 Outside rear annular bearing. 

537 Inside rear annular bearing. 

538 Sleeve on spindle rear axle. 

539 Locknuts for rear wheels. 

540 Lock nut washers for rear wheels. 

541 Dog clutches. 

542 Inner axles, right and left, same length. 

544 Rear outside axle including top bearing of driv¬ 

ing shaft, hub brake supports, rear Springs, 
supports, screw cover for gear case, auxiliary 
bearing caps and truss rod. 

545 Differential gear complete. 

546 Large bevel gears. 

547 Bevel pinion. 

548 Annular bearings on differential. 

549 Large nuts on differential for adjusting bear¬ 

ings. 

550 Lock washers between adjusting nuts on dif¬ 

ferential. 

551 Ball thrust bearing. 

552 Nut back of ball thrust on differential. 

553 Spur gear inside of differential. 

554 Spur pinions inside of differential. 

555 Bolts holding spur pinions in differential. 

556 Holders for rear spring bumpers. 

557 Rubber for bumpers. 

558 Lock springs for dust caps. 

559 Auxiliary bearing caps inside of gear case. 

560 Spring hooks for large and small brake bands. 

561 Large brake bands. 

562 Small brake bands. 


563 

564 

565 

566 

567 

568 

580 

581 

582 

583 

584 

585 

586 

587 

588 

589 

590 

591 

592 

593 

594 

595 

596 

597 

598 

599 

600 

601 

602 

603 

604 


707 


The Automobile Handbook 

Hardened steel wearing plates for large and 
small brake bands. 

Cam shaft for large brake oand. 

Cam shaft for small brake bands. 

Spiral springs for large and small brake bands. 
Levers on cam shafts. 

Supporting pins for large and small brake bands. 
Truss rod under rear axle with two nuts’. 

Cam shaft washer for large and small brakes. 
Eight hand front fender with irons. 

Left hand front fender with irons. 

Bear fender with irons. 

Driving shaft with nut for pinion and cross pin. 
Annular bearing on driving shaft back of 
pinion. 

Annular bearing at front end of driving shaft. 
Adjusting nuts on driving shaft. 

Lock washer for adjusting nuts on driving 
shaft. 

Swivel hub front bearing support for driving 
shaft without bearing. 

Sheet steel dust washer over bearing and screws 
for same. 

Felt dust washer over bearing. 

Swivel yoke. 

Swivel yoke bracket. 

Hinged tee for swivel yoke. 

Steel bar through swivel yoke bracket. 

Special cap screw holding swivel yoke to top 
driving shaft bearing. 

Three-eighths cap screw holding top bearing of 
driving shaft to tubular casing. 

Universal joint, main hardened steel portion. 
Squares in universal joint. 

15-16 i"^h cross pin through driving shaft. 
Sleeve for universal joint. 

Eawhide cover for universal joint. 

Cap screws in universal joint sleeve. 


708 

605 

606 

607 

608 

609 

610 

611 

612 

613 

614 

615 

616 

617 

618 

619 

620 

621 

622 

623 

624 

625 

626 

627 

628 

629 

630 

631 

632 

633 

634 

635 

636 

637 

638 

639 

640 


The Automobile Handbook 

Nuts on universal joint. 

Washer between nuts on universal joint. 
Fender brackets riveted to frame. 

Fender studs for runningboard. 

Pressed steel frame with parts riveted on in* 
eluding front and rear spring loops. 

Front spring loop, right. 

Front spring loop, left. 

Rear spring loop, right. 

Rear spring loop, left. 

Front spring brackets. 

Rear spring brackets. 

Brake and clutch shaft brackets. 

Rear springs. 

Rear spring links. 

Front spring links. 

Bolts and nuts for front and rear spring links. 
Bolts and nuts for attaching front spring to 
loop and rear spring to bracket. 

R. H. front runningboard supporting iron. 

L. H. front runningboard supporting iron. 

Rear supporting irons for runningboard. 

Right hand runningboard with brass edge strip. 
Left hand runningboard with brass edge strip. 
Brass edge strip around runningboard. 

Rubber mats on runningboard. 

Tonneau steps. 

Tonneau step brackets. 

Rubber mat for tool box. 

Battery box. 

Tool box. 

Dash brackets. 

Rear locker box. 

Tail lamp bracket, brass plated. 

Front lamp brackets, brass plated. 

Right hand side lamp bracket, brass plated. 
Left hand side lamp bracket, braas plated. 

Wood dash. 


The Automobile Handbook 


709 


641 Aluminum dash shield. 

642 Foot pedal bracket. 

643 Shaft through foot pedals. 

644 Brake foot pedal. 

645 Clutch foot pedal. 

646 Throttle pedal. 

647 Tapered washers between clutch, brake and 

throttle pedal. 

648 Square tube under dash. 

649 Aluminum clutch with leather and springs under 

leather. 

650 Leather on clutch. 

651 Springs under clutch. 

652 Clutch hub. 

653 Clutch hub sleeve. 

654 Ball thrust bearing back of slide. 

655 Clutch slide. 

656 Clutch yoke. 

657 Special cap screws for clutch yoke. 

658 Clutch shaft. 

659 Clutch coupling. 

660 Clutch coupling sliding squares. 

661 Clutch coupling bolt (long). 

662 Clutch coupling bolt (short). 

663 Large spiral spring in clutch hub'. 

664 Large hexagon head cap screw holding spiral 

spring in clutch hub. (Clutch stud.) 

665 Tapered pin and nut inside of clutch stud. 

666 Thrust ball bearing and two washers on clutch 

screw. 

667 Clutch buffer complete with leather covered 

button. 

668 Clutch buffer brace. 

669 Clutch buffer button. 

670 Hexagon nut holding steering wheel on stem. 

671 Steering chuck. 

672 Steering stem with throttle and spark rods and 

worms. 


710 The Automobile Handbook 

673 Steering post with knurled nut at top. 

674 Spark collar. 

675 Throttle collar. 

676 Steering wheel with ratchet. 

677 Ratchet and screws for steering wheel 

678 Spark lever on wheel. 

679 Throttle lever on wheel. 

680 Nut holding spark lever to rod. 

681 Dust tube on steering chuck. 

682 Dust tube packing nut. 

683 Spark bell crank lever. 

684 Bracket for spark bell crank lever. 

685 Timer rod. 

686 Throttle shaft with levers and throttle cam, 

687 Throttle shaft brackets. 

688 Rod and adjuster to throttle pedal. 

689 Carbureter rod and adjuster. 

690 Carbureter. 

691 Carbureter intake pipe with flange. 

692 Pipe nipple for carbureter. 

693 Carbureter air pipe. 

694 Auxiliary air inlet for carbureter. 

695 Brake hand lever. 

696 Brake hand lever slide. 

697 Special screws in brake hand lever slide. 

698 Controller hand lever. 

699 Controller hand lever catch. 

700 Grips for controller and brake hand lever. 

701 Tension rods and ends for controller and hand 

brake levers. 

702 Brake lever shaft with intermediate brake lever. 

703 Controller lever shaft. 

704 Short gear shifting lever. 

705 Spiral springs for hand brake and controller 

lever rods. 

706 Bell crank clutch lever. 

707 Brass hexagon nut for controller shaft. 



Transmission Gear, 





























































































































































































































































































































708 

709 

710 

711 

712 

713 

717 

718 

719 

720 

721 

722 

723 

724 

725 

726 

727 

728 

729 

731 

732 

733 

734 

735 

736 

737 

738 

739 

740 

742 

743 


The Automobile Handbook 


71J 


Collar for controller shaft. 

Brake and clutch slotted clevises with adjust¬ 
ing. ends. 

Adjusting ends for all brake rods and for brake 
and clutch slotted clevises. 

Slotted clevises. 

Clutch tension rod. 

Long tension rod for hub brakes. 

Left outside brake tubing, with levers and 
offset levers and bracket and muffler support. 
Right outside brake tubing, with levers and 
offset levers and bracket. 

Inside shaft with lever and offset levers. 
Equalizing levers on outside shaft for large 
brake. 

Cross bar on equalizing links. 

Springs for equalizing levers. 

Chain for equalizing levers. 

Equalizing link rods. 

Tension rods for large brake. 

Tension rods for small brake. 

Offset levers for large brake. 

Offset levers for small brake. 

Levers on inside shaft for small brake.. 
Interlocking sector. 

Interlocking sector, roller and adjuster. 

Long clutch lever. 

Hub brake cable with clevis. 

Turnbuckle for brake cable. 

Double clamp for foot brake cable. 

Clamp and leather for foot brake cable. 
Position holder for foot brake. 

Ratchet bracket. 

Inside bracket for controller shaft. 

Dust pan under transmission. 

Right side dust pan on side of engine, rear 
section. 


712 

744 

745 

746 

747 

748 

749 

750 

751 

752 

753 

754 

755 

756 

758 

759 

760 

761 

762 

763 

764 

765 

766 

767 

768 

769 

770 

771 

772 

773 

774 

775 

776 

777 

778 


The Automobile Handbook 


Right side dust pan on side of engine, front 
section. 

Left side dust pan on side of engine. 

Front dust pan. 

Starting crank. 

Starting shaft. 

Starting shaft bracket. 

Starting shaft spring. 

Ratchet collar for starting shaft. 

Brass plated nut for starting shaft. 

Steering chuck brace. 

Steering post bushing. 

Worm and shaft for spark lever inside steering 
post. 

Worm and tubing for throttle lever inside steer¬ 
ing post. 

Timer complete. 

Timer and top of governor case. 

Timer plunger spring. 

Timer plunger holder. 

Timer case. 

Timer case and top of governor case. 

Timer contact segments. 

Timer screw cap. 

Timer glass. 

Fiber ring in timer. 

Ball cup in timer. 

Cone in timer. 

Nuts on shaft through timer. 

Governor case. 

Governor upper spider and screws. 

Governor lower spider and studs. 

Governor weight pivot. 

Governor shaft. 

Governor arms and pins. 

Governor weights. 

Governor springs. 


The Automobile Handbook 713 

779 Bronze bushing in timer. 

780 Long spiral spring holding timer. 

781 Insulated bushings for timer case. 

784 Muffler. 

785 Muffler pipe. 

786 Union nut for muffler pipe. 

787 Muffler cutout valve. 

788 Rear end of muffler complete. 

789 Muffler spiral springs. 

790 Muffler sutout lever. 

791 Muffler cable. 

792 Muffler push rod. 

793 Muffler bell crank. 

794 Muffler plunger. 

795 Muffler bell crank stud. 

796 Rubber button on muffler rod plunger. 

797 Gasoline tank under front seat. 

798 Gasoline tank straps. 

799 Gasoline tank supports. 

800 Gasoline tank cap. 

802 Fiber block on dash for wiring. 

803 Fiber block (4 hole) on engine for wiring, with 

support. 

804 Fiber block (2 hole) on engine for wiring, with 

support. 

805 Fiber block (6 hole) on engine for wiring, with 

support. 

806 Fiber tubing for wiring. 

807 Chains and rubber tubing for wiring. 

808 Spark plug gaps. 

809 Spark coils. 

810 Vibrators for spark coils. 

811 Adjusting screws for vibrator for spark coils. 

812 Plug for spark coil. 

813 Dry cells. 

814 Terminal nuts for dry cells. 

815 Wire connectors for dry cells. 


714 

816 

817 

818 

819 

820 

821 

822 

823 

824 

825 

826 

827 

828 

829 

830 

831 

832 

833 

835 

836 

837 

838 

839 

840 

841 

842 

843 

844 

845 

846 

847 

848 

849 

850 

851 

852 

853 


The Automobile Handbook 


Storage batteries. 

Snap switch for dynamo. 

Automatic cutout. 

Snap switch for lights. 

Electric light globes for side and tail lamps. 
Dynamo. 

Brush holders for dynamo. 

Carbon brushes. 

Coil nuts for coil connectors. 

Sockets for side and tail lamps. 

Dynamo governor with spring. 

Dynamo rawhide pulley. 

Bronze bearing bushing, lower end. 

Wiring shield on front of dash. 

Clevis pins, long. 

Clevis pins, short. 

Clevis pins for spark and throttle. 
Compression relief rod. 

Oil tank. 

Oil tank strap. 

Oil tank cap. 

Pet cock on oil tank. 

Oiler with case complete. 

Oil pump pulley on oiler. 

Flexible tube to oiler. 

Stop cock to oiler. 

Caps for adjusting stems on oiler. 

Sight feeds on dash. 

Glasses for sight feeds. 

Plungers for sight feeds. 

Plunger springs for sight feeds. 

Pipes from oiler to sight feeds. 

Pipe to engine crank case, long. 

Pipe to engine crank case, short. 

Pipe to engine main bearing. 

Pipe to clutch slide. 

Pipe to transmission. 





































































































































































































































































854 

855 

S56 

857 

858 

859 

860 

861 

862 

863 

864 

865 

866 

867 

868 

869 

870 

871 

872 

873 

874 

875 

876 

877 

878 

879 

880 

881 

882 

883 

884 

885 

886 

887 

888 

889 

890 


The Automobile Handbook 715 

Pipe to rear system. 

Unions for ends of oil pipes. 

Oil packing nut at pulley. 

Pipe to center of cylinder crank case. 

Bracket for oiler. 

Belt for oiler one-fourth inch diameter. 

Belt hooks for oil belt. 

Radiator. 

Radiator filling cap. 

Top hose for radiator. 

Bottom hose for radiator. 

Clamps on hose. 

Hose nipple. 

Radiator fan. 

Radiator fan braces. 

Radiator fan bearings with shaft. 

Tee in bottom of pump. 

Plug in tee in bottom of pump. 

Drain cock in bottom of radiator. 

Fan belt. 

Fan pulley attached to fan. 

Hood. 

Hood fasteners with springs. 

Radiator brace, right. 

Radiator brace, left. 

Fan pulley on crank shaft. 

Auxiliary gasoline tank. 

Front bracket for auxiliary gasoline tank. 

Rear bracket for auxiliary gasoline tank. 

Pipe from main to auxiliary gasoline tank. 

Pipe from auxiliary tank to carbureter. 

Pet cock on bottom of gasoline tank. 

Stop cock on bottom of gasoline tank. 

Air pipe from auxiliary gasoline tank. 

Cap on air pipe on dash. 

Oiler pulley on crank shaft. 

Transmission complete with universal joint and 
coupling. 


716 


The Automobile Handbook 


891 Transmission case complete with cap for reverse 

bearing. 

892 Eear main bearing sleeve complete with univer¬ 

sal joint, stationary tooth clutch, gear and 
annular bearings with adjuster. 

893 Eear main bearing sleeve. 

894 Lid for top of case. 

895 Winged nut for lid. 

896 Stationary tooth eluten. 

897 Bushing for stationary tooth clutch. 

898 End adjuster ring tor roar main bearing. 

899 Locking keys for end adjusters for main bear¬ 

ing and counter shaft. 

900 Fillister head screws for locking keys. 

901 Stud holding annular bearing on stationary tooth 

clutch. 

902 Felt washer in long bearing end. 

903 Large felt washer for short bearing end. 

904 Small felt washer for short bearing end. 

905 Main shaft. 

906 Collar on main shaft between annular and clutch 

coupling yoke. 

907 Counter shaft complete with gears. 

908 Counter shaft bearing sleeve. 

909 Adjuster for counter shaft. 

910 Collar between 18 and 28 tooth gears on counter 

shaft. 

911 Collar between 28 and 34 tooth gears on counter 

shaft. 

912 Collar between 18 tooth gear and annular bear¬ 

ing on counter shaft. 

913 Collar between 34 tooth gear and annular bear¬ 

ing on counter shaft. 

914 Counter shaft. 

915 Eeverse shaft. 

916 Eeverse shaft spring. 

917 Eeverse bearing bushing. 

918 Eeverse bearing plug for front end. 


919 

920 

921 

922 

923 

924 

925 

926 

927 

928 

929 

930 

931 

932 

933 

934 

935 

936 

937 

938 

939 

940 

941 

950 

951 

952 

953 

954 

955 

956 

959 

960 

962 

963 

964 

965 


The Automobile Handbook 


717 


Reverse bearing cap. 

Guard for sliding reverse pinion. 

Five-sixteenths inch dowel pin. 

Plug in bottom of case. 

Large rear annular bearing on universal joint 
in long bearing sleeve. 

Small annular bearing in long bearing sleeve. 
Annular bearing on main shaft, in front of case. 
Annular bearings on counter shaft. 

33- tooth gear on stationary tooth clutch. 

Sliding pinion and clutch on main shaft with 23 

and 17-tooth gears. 

18- tooth gear on counter shaft. 

34- tooth gear on counter shaft. 

28-tooth gear on counter shaft. 

14-tooth gear on reverse shaft. 

19- tooth gear on reverse shaft. 

Tubing for shifter rod. 

Stuffing box for shifter rod. 

Shifter rod. 

Sliding pinion yoke. 

Pinion shifter connecting rod. 

Pinion shifter connecting rod end adjuster. 
One-half-inch studs for main bearing. 

Clutch coupling yoke. 

Upper crank case of engine. 

Lower crank case of engine. 

Crank bronze bushing flywheel end. 

Crank bronze bushing gear end (short). 

Crank bronze bushing gear end (long). 

Long bearing cap flywheel end. 

Short bearing cap gear end. 

Crank bronze bushing under hangers. 

Hanger bearing caps. 

Crank shaft. 

Crank shaft gear. 

Cylinders. 

Loose gear cover for pump and cam gears 0 * 


718 The Automobile Handbook 

966 Hanger bearing studs. 

967 Timer bracket on cylinder. 

968 Copper liners for connecting rods. 

969 Pistons. 

970 Piston rings. 

971 Piston pin set screws. 

972 Piston pins. 

973 Connecting rods. 

974 Connecting rod busking, upper end. 

975 Connecting rod bushing, lower end. 

976 Connecting rod studs, lower end. 

977 Connecting rod stud nuts, lower end. 

978 Connecting rod stud, upper eud. 

979 Connecting rod stud nuts, upper end. 

980 Cam shaft. 

981 Cams. 

982 Cam shaft gear. 

983 Cam shaft bushings. 

984 Cam shaft bushing cap. 

985 Valves, both intake and exhaust. 

986 Valve caps. 

987 Valve lifter cages. 

988 Valve lifters assembled. 

989 Valve spring washers. 

990 Valve springs. 

991 Valve spring washer keys. 

992 Spiral gears % in. bore, 

993 Spiral gears % in. bore. 

994 Inlet flange connection to carbureter. 

995 Loose inlet flange. 

996 Double tapered nipples for inlet and exhaust- 

pipes. 

997 Water pipe, horizontal outlet to radiator. 

998 Water pipes, horizontal inlet. 

999 Vertical water pipe. 

1000 Waterpipe gaskets. 

1001 Water pipe studs and nuts. 

1002 Exhaust pipe, cast iron. 


1003 

1004 

1005 

1006 

1007 

1008 

1009 

1010 

1011 

1012 

1013 

1014 

1015 

1016 

1017 

1018 

1019 

1020 

1021 

1022 

1023 

1024 

1025 

1026 

1027 

1028 

1029 


The Automobile Handbook 


719 


Exhaust pipe, front section; exhaust pipe, rear 
section. 

Clamping bars for exhaust aud inlet pipes'. 
Inlet pipe cast iron. 

Inspection plates. 

Inspection plate screws. 

Flywheel. 

Flywheel countersunk bolts for attaching fly¬ 
wheel to crank flange. 

Flywheel hexagon bolts for attaching flywheel 
to crank flange. 

Flywheel bolt nuts. 

Gear pump complete. 

Pump case. 

Pump case cover. 

Pump gears. 

Pump gear shaft, long. 

Pump gear shaft, short. 

Pump packing nut. 

Pump packing gland. 

Relief cocks, % in. 

Drain cocks, % in. 

Priming cups. 

Spark plugs. 

Spiral gear shaft collar on upper end. 

Spiral gear cov^er. 

Spiral gear timer shaft. 

Spiral gear shaft, lower bushing. 

Spiral gear shaft, upper bushing. 

Crank case vent. 


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